The short answer to what functionality should be included in lua is:

If you can do it via the GUI then you should be able to do it programmatically :)
OK that's a bit over the top for a start and I know you need to prioritize.

So, here are a two things I've been waiting for

1) Would it be possible to get the information on the bases that we get from the tab? Base, score, clashing, etc.

2) I know this one could be harder, but could we either have a pull function or (even better) a way to only anchor one end of a band?

I think I could soar right into the middle of the pack with these functions.