Thanks for playing and for the comment.
> i'd like the game to be larger (instead of having a big black border around it) and fullscreenable
Are you using a high dpi monitor by chance? I found out with this game that the framework I'm using has an issue with high dpi monitors. I'm trying to get it fixed, but I don't have a high dpi monitor, so I can't test myself.
As far as your other suggestions go, I think they're all great!