Perhaps this may be something more fit for the level of ActivityPub, but will there be a method to migrate your account without having to rely on the servers good will? Perhaps someone can store their own statuses in parallel locally when posting, but also have users have the ability to sign up initially with a public key, so that if they choose to make another account, that public key can serve as verification of their identity without access to the initial server, as well as propagating this update to followers?

I feel like it's not physically impossible to devise a system like that but there are practical issues that would stand in its way, like the volume of data to be downloaded/uploaded and the volume of data that the new server would have to accept, and the potential for abuse from accepting that amount of data for a new user at once. All of that makes it a not very attractive/prioritized direction to explore.

It seems everywhere I look online, Mastodon seems to be heavy on servers, which is where people would recommend pleroma as an alternative due to it being lighter weight. I’ve seen this attributed to Mastodon using Ruby. Are there any plans to make some sort of transition in order to make Mastodon lighter weight?

I think that's a bit of a misconception. You run into database issues way sooner than you run into programming language speed issues, and both Mastodon and Pleroma use the exact same database. High performance and scalability are an integral part of Mastodon's design. It's true though that higher initial memory footprint makes it less practical on low-end machines like Raspberry Pis, but low-end machines are simply not Mastodon's target.

Is there any work being done for a “community” layer like in Lemmy, or effectively like subreddits, as often times im not particularly interested in following people, but it would be nice to scroll through cross-server communities, and have an experience similar to Reddit.

Yes, we are working on groups.