Although it’s possible to follow Lemmy’s communities in Mastodon, I would not suggest it as the experience is not the same. That’s my reason to have separate accounts.

If you only want to be “notified” of new posts in a given community, I think you can subscribe to some sort of RSS feed. In Calckey (now Firefish), you can add timelines that will show specific RSSs.

Same issue here. It seems most users prefer mobile apps to browser lemmy as many people use wefwef/voyager, which for me, it renders the thumbnails too big and it’s a huge waste of space when used in standard browser.

I found this interface called photon which renders the thumbnails using a decent size but I think it’s still in beta and it lacks some functionality like sorting the answers.