I would love to see a payload generator tool. The way it works is this:
1. Layout your map / payload route (train tracks - just the main route don't add in extra routes till afterwards)
2. Indicate where you want the cap points to be
3. Press start
4. The program puts in the payload and all the pathtrack nodes at the correct height from start to finish and then setup the game logic for you so you can start testing right away!
this would be very easy to do in theory.
you'd basically have the program read in the vmf, identify the models used and their location/orientation. then it'd use pre-defined templates as to where to put the path_track nodes to give smooth corner turns, etc. whilst linking them up as it goes
the only difficulty i can see is that almost every payload track i've ever seen has gaps or overlapping between the track models. or worse, has track models partially underground for ramps.
- so to use such a tool there'd need to be some thought given to having some standards about how to construct the track.
edit:
i might give a random track generation program a go however (e.g. linked path_tracks + models only)
also in terms of if it's worth doing or not, i dunno about others but for me it'd be on the merit of if it sounds like an interesting or fun thing to try and implement in code rather than how badly it's needed or how easyit is to do in hammer.