Whitelists
So I'm in one guild but I mostly play with another guild.
I'd like to be able to hop guilds, but I don't want to abandon my current guild, and I don't want to have to pester or wait for an officer to sign in.
Solution: Whitelists. Players can be flagged to automatically be accepted into a guild, and those players can choose to join that guild at whim.

It's an inelegant solution perhaps, but it would be neat.

Blacklists
So I played some rounds of PvP and in two of them, a certain player announced before-hand that he would feed points to the other team unless we filled the bribery meter.
The second time this happened, I quit. I have a strong desire to never be matched with that player, ever again. I would really like it if ignoring a player prevented me from being placed on the same team as that player.

These are my suggestions. Thank you for your time.