Well, I can only help with POR and CSR. I have never stayed at CBR and really have no desire to. We have stayed at POR twice and CSR once. Both stays were lovely. POR is wonderful, and I think I prefer it to CSR. Now that they are remodeling and putting in queen size beds, it will be even better! We loved the queen sized beds at CSR. POR is big depending on what room you end up in, but it still seems very cozy. We like the food court, and eat there every day at some point. I was not a fan of the food court at CSR. That was really my only issue with CSR, but I probably wouldn't want to be there during a massive conference. The pool is wonderful, but if you are going to CSR for the extra amenities like the workout room, it is like a million miles away. We were very centrally located to the pool and El Centro, but everywhere else was a hike, so I never made it very far. It was an excellent resort to be sick at. I can tell you that b/c I was very sick there. I enjoyed my queen size bed very much whilst ill. That won't matter once the refurb is complete at POR. I never have an issue sleeping there even in a double bed. The only issue is that my daughter likes to roll on top of my face like a starfish. Once I pried her off I was fine!
Ok, I know I rambled a bit, but if I were to recommend a new place for you to try, I think it would be POR, especially if you like the feel of POFQ. And, as a bonus, if you want, you are able to visit POFQ by walking the path or hopping on a boat. Just in case you miss POFQ. From what I understand, they are doing nightly movies on the lawn at both POR and POFQ now, and also have firepits at both locations, so that is cozy.
I can't say where you should request to stay at POR, b/c the really close places are preferred buildings. I was put in building 14 b/c I sent in a letter letting them know how much I loved their resort, but also that it was very difficult for me to walk all the way to the back of the resort in the first building we were in during our 2010 stay. I have a slight disability that becomes exascerbated by all the walking at Disney. It was wonderful when we got there and found our building was about 30 feet away from the food court!!!! My feet were great the whole trip. I am very grateful to POR for that. The best you can do is put in the request if you aren't willing to pay for preferred, and hope they are able to put you where you want.
At POR and CSR we were close to bus stops. I would say we waited a little longer at CSR than at POR though. If I had to guess which resort I think you'd prefer, I would say it would be POR, but like I said, both are beautiful. Good luck! Oh, btw, we are staying at POFQ this year, and are super excited! I always wanted to walk or boat there to visit, and never made it. Yay!!!