Someone mentioned above opening up the API for modders. This would be the single best move the company could make in my opinion - there are a few things that are hardcoded and provide limitations to what mods can accomplish. Easier than coding in the ability for the engine to handle those things would be to externalize everything - buildscripts, instruments code, gravity 0 being 0 instead of nil (so that it can be influenced, as it can be with any number value), that sort of thing. Adding a global tables access function so that we can have windows read arguments and techs check player table things - this stuff would be a huge boon to us who want to push the game a little further. There are numerous old dead threads about all of the things I've mentioned and many others I have not. If the devs consulted some old veterans like bk3k I'm sure they could get a list of things that would significantly improve the possible quality of mods, and most of them would not even be large or difficult edits. Reworking the music system would like as not be the toughest of the things I've mentioned.