Here's a few things I wouldn't mind seeing:
Procedurally generated evac steps/platforms outside of the simple "catwalks" option, maybe via a mesh in the supports files? I know you can use an invisible track segment to make your stairs connect to the ground, but this doesn't make it possible to snake them around (at least not easily), and it also doesn't help recreate segments which have a stairs coming out from the middle of a platform like this:
It would also make it possible to "smooth" fork transitions with a platform underneath like this:
A light switch option - I know this sounds dorky, but I don't like that the catwalk lights automatically come on at night then go off in the day. I know some parks do this, but at my park, we don't turned the lift lights/block lights on unless we have a shutdown at night and a train was stopped there. Even in a shutdown, if there's no train on the lift, we don't turn the lift lights on. We only turn them on in occupied blocks, and even then, often only if we're going to do a walk down. For normal night ops, those lights are off, which I think really adds to the thrill. I also plan to re-create Drachenfire in as much detail as possible, including one of it's most amazing and unique features: The trains had red strip lighting on them, but the track had no lighting at all, giving you a red blur as the trains went along at night!
More options for storage rails: I'd love to see brakes instead of "feeders or no feeders" as your only options, and maybe the freedom to adjust their speed and pressure force? Right now, B&M coasters back into the train barn at the same speed as normal transports, which is not the case in my experience. Usually they back in very slowly, to make sure the transition from track to maintenance rail occurs safely, yet there's no options I can find to adjust this the same as transports/lifts and all the other track types.
It'd also be nice if you could simply click a check box for "B&M maintenance style" on track options, so that it automatically puts an L beam for the trains to sit on, and only removes the rail/ties portion of the track, leaving the spine and feeders in tact. I'd also love it if when you add catwalks to a storage track, it puts them in a "maintenance position." For example on a B&M inverted coaster, instead of putting catwalks under the trains, it would put them above and slightly outside the trains, and have no safety handrail.
I'll be working on scripts soon to do some of this, but it'd be nice if they were just default options!