Thanks, that's really cool! And I'm also glad to be in a position to financially support this project at least a little bit.
Something I think would be cool is either having line of sight go into multiple directions (up, down, left, right) or maybe locking an actor's direction (having them be able to move up and down while always facing left, f.e.).
Also, automatically scrolling backgrounds would be great!
That would for sure help me with the game I'm currently working on using Shimmer Engine (sort of an endless runner)!