Took a look at the Android codebase for mastadon @ https://github.com/mastodon/mastodon-android, and there's definitely avenues for improvements that can be made!
Contemplating whether it's worth refactoring all of the java code there... or most likely, I think I'm going to take a stab at building a full flutter based cross platform (maybe even web) client.
Need to buy a domain first and read through the client development policies - as well as get a copyright release from the employer.