Some 3/4th-dead (a.k.a pretty much abandoned by devs, with barely any community) games I can recommend that could be played in a group are Archeblade and GunZ 2: The Second Duel. They're both on Steam, appearance-wise you can pretty much get most customization items with the in-game currency.
Brawlhalla is pretty good, you can get it in Steam. It's kinda like Super Smash Bros. but 2d and different characters.
If you like VNs, Sepia Tears is a visual novel that plays with your tears. Not an eroge, but a vn like a storybook romance. Has some comedy. It's free in Steam.
http://store.steampowered.com/app/473770/ I've discovered it just today, and it's surprisingly very fun and also quite solid for being a free game! You should definitely try it if you're into futuristic race games such as Wipeout