we have stayed at both AKL and CSR...IMHO, CSR has some of the best bus service on the property. It really seemed liked it didn't take very long to get to any of the parks from CSR. AKL bus service seemed fine as well...although it did seem like the bus stop was a little bit of a haul from our room at AKL though...to be honest, I have never really encountered terrible transportation from any of the resorts on a regular basis...for the most part, transportation is pretty good at all the resorts considering how many people they move around each day...
I think there are water view rooms in all the sections at CSR...If you want to be closest to a bus stop as well as El Centro; you would probably want the Casistas or Cabanas 9B.