As you dont plan to OC, I have dropped the K model and taken a standard 4670, along with dropping the OC chipset of the Z87 based motherboard. This can squeeze under budget and give you the power of the GTX780.
The SSD is just for the OS to install, the 2TB seagate is for everything else.
If you plan to RAID, or would like the option to, then go with Scremin34Egl's suggestion. It should be a slightly higher quality of build based on the H87 chipset.
Ok so go for H87-PRO? what about Gigabyte's GA-H87-HD3 as Scremin34Egl suggested or stick with H87?
Both the Asus and the Gigabyte are top quality brands. The Asus and the Gigabyte are pretty similar and have the same chipset apart from the price difference. Both are solid boards