i would advice against the msi seahawk 1080, i dont think youll get much help from the water cooling so you could save a bit of money there if you wanted to. im using the g1 gaming 1080 and it works fine for $650
i also have the 4790k which works well also. the only thing i would suggest is maybe just go skylake. its not really "needed" but i think its nice to have extra ram slots and imo a better mobo. i cant say for sure that skylake is better for "2k" since i dont own skylake but i believe it is based off of the random web browsing ive done on builds (ddr4 vs ddr3 would be a nice upgrade)