Miami is the worst in my opinion, but Charlotte is usually pretty good, and now that AA flies out of Charlotte, that opens up more options.
My flights originate in Chicago, and I have had lots of experiences (good, great, bad, and terrible) with ORD so I am not an objective commentator - but it is out of the way from the East Coast anyway - and so not a good choice for the OP.
I have also had some good experiences and some of our worst experiences in Houston, Tampa, and Fort Lauderdale so that is a mixed bag and I just take my chances.
In general, I try to avoid Miami and Atlanta if possible.
Global Entry is a very good suggestion and it makes things a lot easier in most locations.