Wow, it looks like you have put some time into this one! Everything looks solid, and your case is one of the few out there that can actually support that cooler.
This is just my 2 cents on the matter, so take it how you will.... but.
You mention at the very beginning of your post that you are looking for a future proof setup. However, the "future" was released a few days ago, and it is a completely new socket and chipset. Intel moved away from the LGA-1155 (from the past 3 processor releases) and went to the LGA-1150 (Starting now) so if you went with the system that you are looking at above, that's where it would end. You would have to replace both the CPU and MB in the future.
That said, all 4 of your choices are solid, you can't go wrong with any of them. The Maximus is definitely the best out there, but it's pricey. If you are planning on OC'ing like you mentioned and can't get the Maximux, I would go with the Sabretooth (5 year warranty ftw!) or the Gigabyte board.
The P8's are generally not boards that overclock super well compared to the RoG or TUF boards, but should still give you a solid stable 4.5
Core i7 4770K and Gigabyte Sabertooth Z87 Motherboard.
Change GPU to GTX 770. Its slightly faster and better with games at about $5 more.
Everything else is superb.
I second the idea of switching to Haswell, but as for the motherboard, since you aren't going to put your system on a benchtable all day, the thermal shield of Sabertooth won't be very useful. MSI Z87 MPower would be my pick instead.