Deus Ex: Human Revolution is slow-paced. It has rpg and stealth elements, fucking love that thing.
Call of Juarez Bound in Blood is my favorite "pure" first-person shooter. The story is not award-winning material, but it's good imo.
If you're feeling really oldschool, there's stuff like Doom and Star Wars Dark Forces. They can take some tweaking to configure modern controls (like strafing), but they're pretty fun games if you like oldschool fps.
Other than that, there's the obvious Bioshocks and Half-Lifes out there.








