Keyboard shortcuts
TTdx has lots of good keyboard shortcuts. It could be even better: Why not assign the numeric keyboard '+' to 'Zoom in' and the numeric keyboard '-' to 'Zoom out'?
The letters 'C' and 'Z' are in use, but what about the rest of the alphabet? Try 'T' for 'my Trains'; 'B' for 'my Buses'; 'S' for 'My ships'; 'A' for 'My Airplanes'.

the menu items along the screen top can be reached by the F keys: F1...F12, then Shift-F1...Shift-F12. But single keyboard strokes are much more useful than double ones; so the single stroke keyboard shortcuts should be optimized. My suggestion:

Rearrange the menu items along the screen top, so that 12 of the ones in most use come first, corresponding to F1...F12. This means:

Move right: Subsidies, player info, profit graph, league table, fund new industries (F6, F9,F10,F11,F12). these are rarely used, when playing one's own game.

Move left: Query tool - used a lot! and, for F9-F12:
the 4 'Build' items for rail, road, water, air.

Depots again ...
When scrapping a bus, ship or airplane: why can't the vehicle's load stay in the depot for some time; and get loaded onto the next vehicle created. This would save one 'go to A, UNLOAD' before sending to depot for replacement.
With trains, this works well, if only the engine is exchanged.

Especially for buses and Airplanes: I would like to have 'go to nearest ahead depot' in the destination list! The program's A.S. (Artificial Stupidity) is at it's worst when choosing which depot to go to!
TTdPatch already has 'goto depot' in the vehicle's list of orders.

More and more Vehicles! TTdPatch has already implemented:
- 250 of each: trains, ships, airplanes, road vehicles.
- more 'total vehicles', including train carriages.
- With more cars: more entries are needed in the destination / order list.
Next TT should definitely have wide limits for these. I've seen a number of TTd/TTdPatch saves using a 'vehicle multiplier' of upto 4 or 5. This will be even more needed if my next idea: containers is implemented.

Bigger cars, ships; with containers!
The tiny trucks seem puny even early in the game!
- Why not at some date introduce:
- 2-storey Buses with some Mail capacity; and:
- Large Trailers - carrying a number of containers!
From the program's point of view, this would correspond to trains with a number of varied carriages.
With fewer but bigger cars, road transport could still be interesting late in the game, without one's stations getting glutted. One could combine Mail and Goods near cities; or Goods one way, Wood/Farmstuff the other way.

And same treatment for ships: Multi-use ships with room for X containers of varied type! This might put general shipping back in the game.
Also: container technology would make it possible to e.g. unload a container ship at a transfer station, and let a trailer pick up the mixed stuff, in corresponding containers.

En Route from ... make it work!

The "En route from ..." system - i.e. one vehicle unloads at a transfer station, another picks up the stuff, and takes it on:
This is very practical, especially with oil from oil rigs. But it pays rather low! Probably a bug in the program, but when one unloads e.g. grain in a station which doesn't accept it, the grain gets an age penalty! And if more grain is unloaded on top, before the pick up, another age penalty.
So this bug must be removed, if mixed transport is to be of any use.

Water at high levels - waterfalls?
Yes, like many others I have thought of that. among other things:
Docks at high levels. But from the programmer's point of view, it would complicate things:
All water at levels higher than 'sea' would originally be contained in lakes. If someone lowers a lakeside, how should the water 'behave' ?
Flood ALL lower land?
Or just run down ONE slope tile, then the next ... and form a one-tile river?
If waterfalls are wanted, one has to define their 'game rules'.

In my better-bridges hack I placed a few tiles of water at high levels. The water just stayed there, no spread effect. If one defines water rules as: "No flooding at levels higher than 0", this might work. But then one would need "place water tile" in the menu for changing landscape; in the editor, and maybe also in the game?

And if ships become more interesting:
I would like water tunnels - from lake to lake, for shipping to use!

Metro! - Subways! - Underground stations!

This would complicate the program even more - The save-files might get enormous. They might have to contain info for many levels, like Simcity.
But it would help a little if it were possible to:

• Have signals in tunnel entrances!
• Have one end of a 1-track Railway station in a tunnel entrance!
• Allow bridges over rails with signals; and over 1-track stations!
• With these options added: one could put stations and/or signals in little valleys under the city's main level; the valleys could be shorter than necessary at present; and the city's street network could bridge over them.
• Maybe one could implement the "Tunnel station"? 1 or more station tracks in parallel tunnels, track length = tunnel length. You wouldn't see your train in rhe station, unless one also implements: "Super-transparent hillsides".

In TT the best approximation to a subway can be built around a hilly town, sitting on a ridge.

Variable Stations
Why can't one add station tracks to an existing railway station? A station might then have more than 4 tracks. TTdPatch has this already. My extra ideas:
- and of different length! - and different starting points.
- Tracks 1 and 2: short ones for city trains, close to the centre.
- Tracks 3, 4: length 4 - for intercity PasMail; maybe further out.
- Tracks 5, 6, 7: length 5..7 - further out, for heavy industry trains.

.. \\
... \\ ... ... ... Excuse my ASCII art!
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... ... ...... \\\

Someone else has suggested: sharing tracks/stations with an opponent as a joint venture. This might be offered when you buy at least 50% of that opponent's stock. If so, one should also share depots.
Would the AS opponent flood my well-designed rail system with his lousy little trains?
I haven't really thought much about this one.

2 deep Inca Bridges, over the Apurimac river?
In Peru, I believe the local indians still rebuild, once per year, one of their old "Hanging bridges" made from ropes, lianas etc. I've never seen one, my Peru trip didn't visit the Apurimac. I did swim in the Urubamba river (rightside one) - no piraja!
In TTdx you might raise a 1 tile wide ridge of land across the valley or bay you want to cross; then build the bridge on top of the ridge.
Less elegant and slower than a real 'Inca hanging bridge'.

This picture is from my better-bridges hack on the "Brunborough Bay" game save. The 2-deep bridge hack works, but the bridge graphics look ugly - the bridge middle seems to hang in the air.

In next TT, I would certainly expect to find bridges 2-deep, 3-deep etc. Also maybe: 2-storey bridges! The East-going trains using the lower tracks, the West-going ones the upper.

And why not bridges and tunnels in vertical and horizontal direction?
Since we have rails going that way.

And tunnels with turns? probably too complex, forget it.

The Brown Bridge: bare-land or grass-covered: the Ledge gave me another idea: why not have a plain 'bare land' or grass bridge buildable in any place? Bridge without guardrails, seamless to it's neighbour. the tops of these bridges could be used by towns for roads, houses etc.

The need for this? Imagine two towns on hills, separated by a valley. In the valley 2 to 4 rail lines.
To give the towns building space towards each other, today one would bulldoze those rails; pull up points, forming land at level 2 between the 2 towns, with roads etc, inviting houses. Then one would need tunnels under this, to re-connect those rail lines.
Disadvantage: high cost; long tunnels, long distance between signals.

With my suggested Brown Bridges, no need to tear down old rails. just build a series of Brown Bridges (maybe 2-deep, or 3-deep?) side-by-side; some for roads, some for future houses.
One could leave gaps between some of the bridges, for signals on the rails below.

Another case: a coast town, a long island nearby:
Instead of lots of 'raise sea', one might build a series of Brown Bridges out to the island; then road network. Lots of new house-space for the town.
and: Ships could sail under this structure!
I tried to hack this in my better-bridges hack

The Ledge alongside steep mountains
In TT(d) one finds steep mountainsides, going up 5..6 levels without pause. To build a rail line along this mountain, one needs to pull a number of land points DOWN or UP: a costly process, both in £ pounds, and in trees belonging to those nearby towns.
In real life: one shores up the mountainside a bit, and builds one's rail track on a ledge in the mountainside.
TTd already uses this technology for houses on hillsides! You see small ledges of stone etc, one under each building.
This picture from my better-bridges hack shows my idea of a ledge alongside mountain, for rail (or road). The 'shore-up' stuff could be stonework, as for hillside houses; or legs just on the down side of the bridge.

The ledge might have guard-rails on the down-side, but not on the up-side: Road/Rails on the ledge can have connections going uphill, but not downhill.
This ledge should be built originally as a 'bare land' bridge; then the player could place road or rail on it.
At the ends of the ledge, one needs one pulled-up point, with a horizontal straight edge for Road/Rail to continue on normal land.

What constitutes cheating? in Transport Tycoon
Of course there's always a difference between cheating in your own private game, and cheating in a competition. Each competition should define what's allowed, and what is not.

Sabotage the AI opponents - some regard this as cheating! I do not.
But I don't do it much - I just tried it a couple of times in old TTo.
I prefer to let them help me - lower mountains, clear trees etc for me.
To compete with their ratings: simply use an advert.

Placing trees on fields or sea depots on water for cheaper building - that's just plain technique, not cheating! If there's an expensive way to do a job, and a cheaper way, you should not be required to use the expensive method. This is a game , not religion!

MEGA-stations? As long as there's a station element at the station origin, or quite near, I see no reason for criticism.
Those extreme far-walked stations, 100 tiles or so, in my original TTo example: I don't use them anymore. But Stretch 20, as the standard in TTdPatch, should be allowed.

"Trains reverse at..." - should be the player's choice! But "Reverse at end-of-rail only" does work best.

These I DO regard as cheating, in a competition:

• Straight MONEY cheats - money from doing 'nothing'. But it is useful for trial building!
• Visiting the Editor - enhance one's cities - nice new industries - etc.
  But I sometimes visit the Editor before starting my private game: To remove silly things like long unbroken roads between towns; too many tight street loops in large towns; long tunnels that stop me from tunneling the other way; etc.
• Changing these Difficulty Settings within a competition:
  Breakdown , Subsidy multiplier , Disasters , Economy , Competitors Start and No of.