I changed the mobo because ud3h is great board for the price, and you can still can get good overclocks with it, and i have personally used this board.
i changed the ssd because it has great performance and its 480gb for really good price, and my brother has the same one and he really likes it.
i changed the hdd because the wd black you had can get really loud when loading games and such, and the blue is much quieter and still has great performance.
i changed the psu because i dont know if the evga makes good psu's not, and the corsair hxi has higher efficiency, and it has corsair link which i think is pretty cool, but thats my opinion