My rule of thumb for a balanced gaming PC is to spend twice your cpu budget on the graphics card. It is that important.
In this case, if you are willing to spend $220 on a 3570K($180 @ microcenter), then you should be willing to spend $400 on a GTX670 or 7950 class card.
Now, I would still buy the 3570K because I think it is a 4 year card, and you can always sell and replace your graphics card later.
I see no reason not to buy a cheaper M-ATX Z77 based motherboard. How many expansion slots do you really need?
Here is one for $90:
http://www.newegg.com/Product/Product.aspx?Item=N82E16813157325
You might post the rest of your build parts, perhaps there are some other savings.