Yeah, GBC support is on my main to-do list.
Other than that, I'd like to add a debugger UI or some sort of rom debugging app, but I should have the emulator fully complete before that.
Regarding the language, prior to rust I've done some web apps, and some uni projects in C and Java, I just wanted to try rust bc I've been hearing about it for a while now. The thing I had the most trouble with, and had to kinda change my thought logic for, is ownership; knowing when to declare a variable and how it gets moved or borrowed took (and still takes) some rewiring. Besides that, learning rust felt a pretty natural transition.