Yeah, that should work fine. It's all compatible and shouldn't cause you any issues. You could probably have gotten away with a 650-750W PSU.
3000MHz is a good RAM speed for X99. You can go faster, but 3000MHz is a good balance between speed and stability. It also works on a CPU strap/gear ratio (depends on board manufacturer) of either 1.0 or 1.25. The 1.25 ratio allows for OCing without raising the multiplier up as high. E.g my 5820K is running at 4.1GHz on it's stock multiplier of 33 because I have the strap at 1.25, giving a BCLK of 125MHz. I could run a strap of 1.0, but my multiplier would then need to be 41.
3000MHz is a good RAM speed for X99. You can go faster, but 3000MHz is a good balance between speed and stability. It also works on a CPU strap/gear ratio (depends on board manufacturer) of either 1.0 or 1.25. The 1.25 ratio allows for OCing without raising the multiplier up as high. E.g my 5820K is running at 4.1GHz on it's stock multiplier of 33 because I have the strap at 1.25, giving a BCLK of 125MHz. I could run a strap of 1.0, but my multiplier would then need to be 41.