I just built my computer a few weeks ago in the same (basic) price range and it's working great. For strictly gaming, pretty much any of these builds will work fine (i5 4670k, etc), but for streaming and rendering and such (multi tasking) I love my 4770k.
Case is all personal preference so not much to say there. For cooling, i personally think air is better since its quieter and simpler, and nearly as good but thats also personal preference. Love my 760 and samsung 840 :)
Just to add on streaming, when I switch from playing normally to streaming i dont see barely any frame drops. Even with demanding games like metro and farcry, the fps stays pretty much the same.