I agree with everything expect the CPU. Both the 8350 and the i5-4670 are much better performing than the XEON and for a gaming PC the XEON efficiency/stability is not needed. I would personally go for the 8350. Better value for money. But the i5 is great too.
Only thing with the Xeon is it can't be overclocked. This may not be a deal breaker for the owner though. The xeon's hyperthreading won't help in gaming either. Its only slightly faster than the i5 4670k and if the i5 is oc'ed it will beat out the Xeon. The biggest down side of the FX processors is the AM3+ socket. Its fairly old and a dead end socket, it really has no future for upgrades. AM3+ does have a few years left in it but that's it. If you want to upgrade this PC 5 years from now the Intel socket 1150 may be the better option as you could always grab an i7 down the road.