Also I don't understand the upload torrents limit, ok, limit concurrent uploads, but everything I'm seeding should be available all the time

Well, that's an issue for sure, but in my case it's just that when you have thousands of torrents seeding it's hard to keep them organised and navigate them, labels help but not much, essentially my bittorrent client is a bucket of shared files, reviewing what I have, deleting and moving is a hassle.