Brandon, I think you should buy a 1D4. Equals 25 MP resolution on a full frame, but of course, cropped off down to 16MP. I enjoyed the one I rented...noise not much worse than a 5D3 from ISO 1600 through 6400. Above that it's significantly worse...below 1600, probably slightly worse. Unless you shoot wider than 85mm most of the time, (or at higher ISO most of the time) it's the one to get. Let's face it, it will be 2016 before Canon introduce a full frame sensor with similar (or slightly finer) pixel density to the 1D4. Sure, they'll introduce a full frame with very tiny pixels, but that won't be all that useful outside a studio, or for fast paced work, or for low light/fast work...and it will cost $9k or more.
They have spread out all of their bodies so that even ones like the 1D4, that got discontinued, aren't really getting displaced. A good strategy.