An alternative to Global Agenda (if you've had enough)
Warframe is where its at with the PVE scene that Global Agenda was known well for. Although it doesn't have PVP based modes like GA does, it has WAY more missions than Global Agenda has starting out. Very scalable and easy to jump right in without getting screwed by low level weapons. Also fun to play with friends.
Controls are similar to GA and don't get me wrong, I played the hell out of GA in its hayday. But if you are fed up with GA, try Warframe. Its free to play and is not in any way Pay to Win (even though you can buy ingame "platinum" with real money, you can get those same items with "blueprints". Platinum just makes it go faster). Besides its PvE only so there's really no reason to get mad at someone who has the paid gear that you can get freely.
Digital Extremes does NOT pay me to advertise their game, hell i only started 5 DAYS ago... (its been in closed beta since last October, but went into Open Beta about a week ago).
But its so damn addicting that i recommend it and usually im too lazy to go on a forum and recommend any game let alone a free one...