First things first, way to go on scoring a new ride. As far as Canyon boats, I'm not familiar with the hull, but don't sweat it unless you hear something bad from a reputable source, or experience it first hand.
Regarding your pump setup question, I would say run it as is first to get a baseline. Before anyone could really speculate much on the B impleller they would need current HP/speed figures. The great thing about the DPS (cavitation reducer) is that A. you got it for free (not counting purchase price of the boat) B. It should mask the low end lag of the B cut impeller. Run the boat a couple of times and take notes as to speed (GPS indicated if possible) to RPM etc. Congrats and good luck