Firstly, the thing that sets the DBXL Set out above any others currently out there, is the sheer massive volume of liveries one can use. It's just so prototypical, and expansive, that it's hard NOT to have a nice looking railyard full of rolling stock.
That said...
As each "period" goes through the game, I often wonder how to repaint my fleet. It's easy when I'm getting rid of a class of loco (eg replacing all remaining steam with diesel or electric), but it's very hard to repaint current stock.
An example, perhaps.
The DBXL set is tough. Lets not beat around the bush, those electrics are EXPENIVE. So, when I have a BR140, in the year 2000, in perfectly acceptable condition, with another 15 years left in it, I have two choices to bring it out of it's "bottle green" (I fear the correction of Michael if I got that wrong

What would be nice, is to have an option to "repaint" the locomotive, without actually renewing it's lifespan. 'Cause, lets face it, when I'm looking at a network of all-red locomotives, I'm not going to remember that all those BR140's are needing to be replaced, especially not if the games big enough.
I'll be flat out honest, I don't know if it's something already possible (I know we can have liveries of engines/rolling stock changing automatically at dates, but thats horrible, to see everything repainted all at once, whilst on the move...), or if it would be easy to implement, I just thought I would throw it out there, in the hopes that a patch dev would read it and say "hey, Raichase makes a good point, I wouldn't mind seeing that", and throwing it in.
Certainly not a game-altering feature like some of the stuff we have had recently, but it's just an idea I had while playing my favorite set....
Thanks everyone for taking the time!
Rai