[McGillicuddy]

Interesting. Some anti-fouling bottom paints actually reduce friction by letting air between the hull and the water giving the boat some separation and thus less friction. Assuming the motor is in tune and your fuel is fresh, I would consider a couple of other things before blasting the paint.

If your mph was actually knots, you're probably fine; if indeed your reading was mph, that seems a little low for a 150hp E-tec. You might check your motor height (anti-cav plate should be about 1-1/4" above the bottom of the keel when the two are parallel). If it is too low, it will drag and reduce performance, sometimes dramatically.

How big is your fuel tank, 40 or 70 g.
Also might identify your prop model which may help one of the prop wizards to determine if the model of your prop and its geometry's desired effect is right for your boat.

Good luck with your MA