I am huge on performance per dollar, and I spend a lot of time hunting down deals.
I build-and-sell gaming rigs on the side, and most fall between $600 and $900.
So.. This section of the SBM always attracts my attention. I love to compare notes.
I think this build is much better thought-out than most of the budget builds I have seen in the last 2 years. You were very thorough, and it's a great build!
However, I find myself disagreeing with this statement about the GFX card: "In fact, for what we had available to spend, we couldn't have done better."
Yes, you could have. (sorry)
The r7 265 offers excellent performance per dollar, but there are better options:
For $120, the HD 6970:
http://www.newegg.com/Product/Product.aspx?Item=N82E16814131578
For $120, the HD 7850:
http://www.newegg.com/Product/Product.aspx?Item=N82E16814150642
For $160: The r9-270. (I don't know where you got $190 from, but they have been under $175 for a while.)
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202090
For $170, The GTX 660:
http://www.newegg.com/Product/Product.aspx?Item=N82E16814125508
(The extra $10 - $20 could have been obtained by selecting a smaller HDD.)
Other than that, this build is spot-on.
I can't wait to see the next budget SBM with the G3258!!