If the API had functions for opening dialog-windows, adding buttons/widgets, reading keyboard-input or even processing sound, it would bring a whole community of useful user-apps for FL Studio and would possibly have the benefit of making life easier for the IL team because the users could add their own functionality instead of nagging you about feature x or y...
BTW the DAW/tracker Renoise already have an excellent API like that (it uses LUA instead of Python). You could perhaps look at their approach for inspiration
