The thing with replacing DeviantArt could be interesting. Sites like that - not just DA but also Fur Affinity, Weasyl, etc - have a very different philosophy about how to show your "feed":

1. there's always a separation between images and text posts from the people you're following
2. no reposts - instead each user has a gallery of "favorites" (essentially your likes, but it's public by default)

These two things are what makes it possible for me to discover artists on sites like these, and why I can't do the same on Twitter, Tumblr, or Mastodon. The tonal whiplash is just too distressing.

I have made a web app called Crowmask that exposes my Weasyl posts to ActivityPub, but unfortunately it's one way only for now (and single-user - I'm not prepared to take responsibility for hosting content from someone I don't know offline).