First thing that I noticed when I looked at your build was the i5-6600k on a H110M motherboard. Is your friend not going to overclock?

When considering to get a CPU, you MUST also consider the chip set of the motherboard. If you want to overclock any motherboard with the "Z" prefix can support OC. If your friend is not planning on overclocking I suggest getting an i5-6500 instead.

Graphics card can definitely be changed. A solid state drive can also be added.

Here is my suggested list (This is something I put together in 5 minutes, so there are parts I will consider changing if a lot more thought is put into it):
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