1: I cant say it will, games can evolved very fast or they can stay like this for a while, The new engines like Crytek and Frostbite 3.0 have just come out so it might be this GPU holds on at maxed out setting for a while, not sure how long, and u can always get another one when they get cheaperr to crossfire
2: Yes, its a very good bang-for the buck CPU, games dont demand a lot of CPU, the games u mentioned should be fine
3: They are both excellent, this gen in particular they are very neck-and-neck, AMD has mantle coming out but noone knows what that will actually do so they are both excellent