Nice idea! Do you think they are different feeds or can you see a merger of all feeds in one as Gmail does?
Would feel similar to notedeck wills been working on?
I don't know if that's what he is making but the idea is to not even have an account switcher. You should be able to like, zap, boost as any account, in a single click without evereaving the mixed feed.
Sounds like a headache. Still have to choose what account to do what from while on the mixed feed when liking, zaping, etc. Like an annoying pop up is what I'm imagining. "What account did you want to like this post from again?" Swiping left or right to change accounts individually I think is the best option. Then users can manage lists(maybe make them shareable between npubs) for mixed feeds? Either way I see choosing what actions are from what account each time very annoying.