Spend the $40 to upgrade to a i5 4670k. I have it and it is amazing. Plus there is a $20 off code so you would only be paying $20 more for it.
Unfortunately do to this whole coin mining fad. It would be impossible to get a HD 7970 (i've seen them before go for around $270 and its more powerful than the gtx760) But the demand for AMD cards to mine litecoins and stuff has skyrocketed the prices for them. So your gpu is great.
I highly doubt you will need another fan with the antec 900. I use the antect 300 (a step down) and it has great stock cooling. The only cooling you need to worry about maybe is the cpu, so throw in one of these
http://www.newegg.com/Product/Product.aspx?Item=N82E16835103065Other than that its great, great motherboard and pretty fast ram.