This thread is going to get BIG!
We have stayed at all the moderates.
I think it really depends on your family, and what you like for theming.
I have heard people say if they live in say Arizona - Coronado Springs *might* not appeal because there is lots of similar southwest theming back home - and it doesnt feel like a vacation. Others feel right at home....Similarly I have heard people with Mobility issues say how much they like POFQ for example, due to its easily accessible layout & intimate feel. I have heard others say it feels too smallish.
Anyways - just keep that type of idea in mind when you hear feedback on this topic.
But that is what is so great about Disney - Something to appeal for everyone!
So I guess my point is - there is no one BEST for everyone.
FOR MY FAMILY - we have no mobility issues, and live in the Northeast...we really like all the moderates...and have no one favorite really... I actually think CBR might be close to our favorite...
We like the tropical feel, and the new zero entry pool and the serene paths...and its a fraction of the price from the Poly.
There is actually a thread here
http://www.mousesavers.com/wdwresortfacts.html#moderate
That might help you with your decision