Good choice on the cooler. It's cheap and the ones that are better are also 2+ times the price (give or take a fiver).
Case is good, I have the 912 model.
I think you are overpaying on the PSU; that said, I do not know what a better one would be.
A better price for the hard drive. It's not the same model or manufacturer, but it's just as good.
A better DVD burner, for cheaper. Plus, you get some money off of media for the drive.
Instead of a free Intel Robots t-shirt, you can get 20$ off
Here, with a promo code. Unless, of course, you really really want that T-shirt.
We can do better on the motherboard, but I have no idea where and what board to replace it with.
We can also do better on the keyboard. That one will NOT really feel like a mechanical one. It also doesn't have very good key rollover (at least in my experience). Spring for a
Das Keyboard or the slightly cheaper but still good
Razer BlackWidow. The BlackWidow has macro buttons, and is a bit lighter. It also doesn't look as cool as hammering out your words on a blank keyboard
For the RAM, use these
G.Skill DIMMs.Get the
EVGA SC 560ti. It's a bit cheaper, just as high performing, and has a good warranty.
The 11$ mouse will fail you. I guarantee it. If you budget allows (or later on), get a
Razer Deathadder. They are solid, not overly spendy, and last a long time. I think (not sure) that they also have a lifetime warranty.