Steve - I was at Lake Powell for a week last summer and launched out of Antelope Point. They have the ramp that is part of the marina, but they also have another ramp operated by the National Park Service. It is public just like Wahweep, and you can leave your car and trailer in their lot for two weeks. The marina is nice, but it is set up mostly for big houseboats. They have gas and a small store and overnight slips, but the restaurant was not open last year and there is no lodging on shore.
I like it because it is newer, less crowded and puts you an hour closer to the best cruising/camping areas. I keep my 22 there now because it is only $38/month on the trailer and they will launch it for $15 round trip.