While giving your speakers more power will improve the sound (Paradigm like juice), it won't give nearly the improvement of upgrading the speakers themselves. If it's possible, haul some of your gear into the dealer to test it. Run your speakers off your 3805, then off the Rotel amp. The Rotel amp will give you more headroom and deliver more clean power, but I really don't think that it will make a big of a difference as new speakers.