A few features left to add, load and save, and import palette (from clipboard)
There's no undo currently and that might not make it to the v1.0 release, I'd prefer to do things like svg export or something else more valuable. (of course some will want Undo at the top of their list....)
Another couple of things that will probably be requested features, are zoom and touch select. I haven't figured out if touch select is feasible, it's a tricky thing to do if you have a lot of layers, not to mention the other touches for angle setting being affected by a touch select gesture. I agree that the select loop system *(the up down arrows on the bottom toolbar.) isn't ideal.
It would really require a fully changed UI and since this is a non-profit product (there's Zero budget to build this.) that's not going to be possible. If people start to offer donations it might be doable, but I'd really want highly specific consensus based UX before doing that sort of overhaul.