Well I think the GM should add a group chat... Some thing like this
/group (user), (user), (user)

Well I guess that can be an update.
And I just got an idea from the forums of lotto tickets?
Well that can be. Buy 1 lotto ticket for 50 CE (or maybe 25 CE for a cheap one 50 for average and 100 for a rare ticket the more expensive the better chance that you will get a better item). You can use it and a button will pop out, Click it and you win random stuff like Costumes accessories, mats and stuff.
How about mini-games? Where you can play games with a friend or random people. Something like Tick-tack-toe... But I think that will make the game less Spiral knights... So put that in hold.
How about PVP.. not like lockdown
Something like the real PVP (Player VS Player) like "1 on 1" When you click the name a new menu will pop out called DUEL.
I think thats all I got for now.