Amazing benchmarks mate. Crysis 3, Hitman and Tomb Raider are all AMD Evolved titles to so those Titans are being held back a little, plus it'll probably be a couple years until a setup with 4 cards is supported on the software side, to the point that they'll be put to maximum use. Oh and the fact that most games aren't even coded with triple figure FPS numbers in mind, so the game engines themselves will be bottlenecking the hardware. Probably sounds far fetched but your FPS numbers will drastically increase as the years go by IMO. The fact that Tomb Raider was running at 200fps at some points is crazy from an engine's point of view. Under perfect conditions I'd put money that a setup like this could run Crysis 3 maxed at 1600p 200+ fps consistent. Hitman is the only one I can compare with myself, but you're getting about 40% extra performance with your 4 Titans than what I get with a single 670 that's also in a rig that's inferior in every other aspect to yours, despite you having about 400% the power. It's a shame that when an amazing rig like this comes along that it's being throttled by so many different factors.
Best rig I've ever seen.