How about the Call Of Duty series? (here me out ;) )
Call Of Duty 1 was my first ever FPS and I loved to death. It would be cool to see the evolution of them. Most people these days only know of the repetitive drivel that is MW and BO and are oblivious to the series' routes and origin. I don't know how many times through I played it (many!) and it would be cool to see its history through the logic of EFMS!