And as I said in my big post, I'd normally recommend a more powerful graphics card. There was, in fact, focus on the GPU - focus that applied to the OP's needs. Fact of the matter is, a 6770 will max out SC2 graphics, so a more powerful card will provide zero extra performance for the two games listed by the OP.
An i5 is a good choice for hobby streamers (for SC2 & moba games at least), and overclocking adds roughly $70-$100 in cost for Intel... yes, buying a new mobo and after-market heatsink could allow an overclock in the future with an i5-2500k (cost $200 @us.ncix.com), but I think it's better to get under budget now and spend more later on a new processor/mobo combo when new equipment is out. College budget and all.
I expect you're right about the RAM.