I'm acting more as a member on this one since I have nothing to do with it, but a couple of ideas I personally found interesting and was wondering what others think. There are quite some promising games, and others we could expand on, even in simple ways.
1)CS:GO Casual
A simple server where we will be able to do some gatherings and fight each other, not having go 1v1 at all times, but more like a DD2 server. Maybe add some implementations to make it more fun-like, but keep the purpose, teams vs teams, 1.6 style.
2)DayZ
DayZ might be progressing at a very slow rate, but it is progressing nonetheless and currently only Rust is competing against it at a very good pace. It is still promising and the last 2 months has gained a whooping 220% increase of players according to Steam Charts.
3)Minecraft
Many people get hyped when this gets suggested, but I'm personally a little hesitant. It didn't reach the roof with its activity if I recall correctly, hopefully people are still interested and will return if its decided to return.
4)Call Of Duty
Many versions, lots of activity, even in the old ones. What kind of server and what version can be decided later, but a CoD server could be an interesting debate.
5)Garry's Mod
Easy one, still popular, could be given a shot.
Simply some ideas on the table, mostly for the sake of a discussion.