There's floatplane... If you are subscribed to that, you can link your MC and floatplane accounts, and get some perks ingame, like coloured text, flying in the lobby, being the first in a queue when joining a server, etc..
Jake is implementing a new ranking system with ores which I think are Iron all the way up to Obsidian and Void e.e. I do not believe you have to subscribe to donate to get these ranks, but rather with in-game playtime and in-game money. We'll find out more when he posts about it though.