I know the +2/+1 floating attributes is probably a WotC thing, but it's kind of silly to have two different mechanics (point buy then +1/+2) to accomplish the same thing. I think you should just have a 36 Point Buy (with 16 and 17 costing 3 points each). That will make the 17/16/15/8/8/8 min/max build viable, but make more balanced builds even better. I personally think it would be fine to buy up to an 18 (for 19 points total), allowing a min/maxed 18/17/10/8/8/8 (or, more likely, an 18/16/13/8/8/8), a "maximally balanced" 14/14/14/14/12/12, or something in between. This is basically the 3.5e point buy system (with no racial modifiers), which worked just fine. I'd also allow you to reduce an attribute to 7.
While purely cosmetic, I'd automatically "spend" 12 points to start characters off with a 10 in each attribute to denote the "average." You could then reduce from average if you wanted.
