If the feed seems to be stagnant, you could be using the (default in many cases) active sort, which tends to have a lot of the same posts at the top, from what I've seen. Switching the sort to hot generally shows more fresh content in my experience. You can block communities on the web version using the red button on the right, in what I think is the sidebar, although that might be hidden on a phone. This site looks to be helpful for finding communities as well.
I uninstalled my reddit client and put my Lemmy client in its place on my home screen so the muscle memory doesn't have to change. Here's hoping the communities end up being a feasible replacement!
What KeePass doesn't do for free is sync across as many devices as you want without issues. For a couple years I was using KeePass + Syncthing, but I kept having sync errors and ended up having to merge databases on a regular basis. Dealing with moving the database around is difficult when you're regularly creating new accounts and authenticating from four plus devices.
I think what OP is talking about is the ability to generate TOTPs, which requires a paid plan.