I know NASA tried to add game aspects to this, but I wouldn't call Moonbase Alpha a game, and if I did, I'd say it was a horrible one. The mechanics and physics of realistic EVAs just don't make for fun gameplay, and leaderboards don't make up for that.
I will call this a great simulator, though. For people like me who are interested in realistic depictions of future space travel (Atomic Rockets FTW), this is a great experience. NASA put a lot of detail into making the EVA as hard as the real thing without making it unplayable. I'd be interested to see if they make more like this in the future.