Most multiplayer games that let players make their own servers, and end up with hundreds or even thousands of servers have things like...
A server favorites and server blacklist. I can see how this can be added into the UI; press tab, and on the top right side, 2 buttons. One button is a heart, and hovering over it says "add server to favorites", or just "favorite server". The other button is a black skull, and hovering says "blacklist server". In the server select screen, add a new toggle for favorite servers, and blacklisted servers. You can't join blacklisted servers, or see them without toggling them on, but you may unblacklist them. I don't know enough about coding to know how difficult this would be to code.
A server rules page. For dedicated servers, which need this the most, I could see this being done with a rules.txt, or motd.txt (something better than a .txt would be nice, for better formatting and pictures) or whatever in the server folder. When a player joins the server, either right before or right after they select their character, they see a screen with whatever text the rules.txt has, and at the bottom, there's an "I understand" button. I, and likely many other people have some trouble with sharing server rules, or letting people know how to contact admins in case of problems. Adding another button to the tab menu to read this at any time would be nice.
I'm sure there are other things that I can't remember, but these 2 are pretty big.