actually MBAs are quite suitable for CS6. I use CS6 ruthlessly professionally. I know a few peers who have MBAs for work (prev gens even) and love them for their portability.
refurbs are fantastic values.They are sold as brand new full warranty. I've bought a few refurbs and wouldn't hesitate to do so again. I can tell you that processors now are more than fast enough for you at this point, your friend, is RAM. And, if possible, an SSD.
Those two items will be the biggest and the most significant speed upgrades than the processor.
Get a 13 refurb, (or base model 15...) and max the ram!! If there's enough savings, get an SSD.
DON'T think of the processor at this point. Trust me. They're all fast. Ram... a quad i5 is really fast, and you'll be more than happy with it.
I currently have the 2010 MBP with just the dual i7 (not quad as the current) and the only reson I'd ever upgrade is to be able to go to 16 gigs of ram form my current cap of 8. I popped an SSD in instead and holy crap what a speed upgrade.
my opinion from using CS6 daily.
