Berkeley is a good choice. BF'r powpow has done the GPC ride you noted above and we both made several of the Tuesday evening hammer fests that they organized in the hills this year - great workouts. The POO ride is well known around here, and several BF'rs ride this one too - it sounds like it would be just what you're looking for. I want to give that a try, but haven't managed to get my act together yet.

FWIW, I live just the other side of the Berkeley/Oakland ridge in Orinda and there's a great number of route combinations open to you - especially if you like climbing. The climbs are shorter than several of the classics on the peninsula, but there's some really good challenging ones in the mix. The roads are in reasonable condition and there are plenty of routes with low traffic/more considerate motorists. If you're looking for longer rides, it's easy to through an out'n back to Diablo for 80-100miles, or ride down Redwood Rd to Palomares/Sierra/Calaveras etc. Berkeley's a great location for many riding options as well as being a stimulating place to live.