I run the same setup with a bob's plate and tsg tabs.
Get a jack plate before you worry about the prop. Trust me. Youll see much greater performance gains with a jack plate than a prop. Get the anti-cav plate 1" or so above the keel and youll gain a few mph for sure.
3 blade 9X9 is perfect for running with a moderate load or two adult males. Overall, this is the best "compromise" between top end and holeshot with the boat loaded for a full day on the water.
3 blade 9X10 will give you a little extra top end while running solo, but with two adults you will lose some top end and LOTS of bottom end/holeshot. If your over 200 lbs and fish with others I would look elsewhere.
I've never ran a 4 blade but that will be my next experiment. Looking to run a little skinnier.