Hitman Blood Money is one the best stealth puzzle games of all time. Hitman Absolution is a good linear stealth action game, but it isn't like past Hitman games at all. Dead Space 2 is a great action game, paced really well, isn't too long or short. Bully is a shitty game, tons of minigames and the PC version is a terrible port. Alien Isolation is great for the first five hours, okay for the next five hours, and I stopped playing because it was gonna be another 5-10 hours of repetitive bullshit.
Arkham City is a great game, good pacing and stays fresh throughout. Mass Effect 2 is good if you're in the mood for Mass Effect, if you aren't in the mood for corny dialog and a dumb story, skip it for now. Max Payne 3 has some of the best feeling shooting in the genre, also has fantastic physics. But there are forced cutscenes and there's a ton of them, not the best game if you aren't sold on the story or lack patience. You get to shoot a ton of shit, but you also have to watch a ton of shit.
The Metro series is complete garbage, but that may just be me. Xcom is a great game but its a good game to have on the side. I'd personally recommend Fallout New Vegas . Great gameplay freedom, a lot of side content that's fun and isn't obtrusive, the main questlines are variable, fun, and don't take to long to beat.