Few things, which will make life better.
1) Auto kick from party members who are offline for more than 30 minutes
why: players usually just turn off the game without exiting from the party, so they just block the slot. Or a random player connecting to the party where few guys are offline already
2) Auto disband party, if all party members are in the safe zone for more than 15 minutes
why: example. Whole AFK party with 1 open slot. Golden Tantalos killed them in the middle of the night. Until morning a lot of players join and exit this "fake" party.
3) The Auto-accept button by default should be activated
why: guys just forgot to click on it from time to time. Players are trying to join the party but the chance of success isn't too big.
These changes will significantly increase the pleasant game experience.