I like the Ultra option, but I'm a li'l biased and unfamiliar with the other choices 'cept for Klipsch. I also think you'd be fine with the Prime Pinnacle towers. You're getting pretty much all of the performance of the Ultra towers minus some bass extension, and your excellent sub choice takes care of that. You'll still be getting more room filling sound where it counts. The Pinnacles weren't out yet when I got the Ultra towers. If they were I'd have gone with them instead.
*PS, My 2nd choice would be the JBLs, but the center channel is definitely a weak link.