I don't know if it would disqualify the OD rating, but I would certainly be happy to race against you. That's a lot of drag.
The boat is manageable with the Martec. Also, as you compare it to your prior experience, remember that the underwater profile of the two boats are likely very different.
The prop wash throws a lot of turbulence across the transom hung rudder on the J30 and I think that's what causes a lot of the issues. I don't see a three blade prop helping that.
My advise would be to practice with the folding prop and figure out how the J30 likes to back up. Before you can apply steerage, you need a little aft momentum, so bump the throttle. Once the boat is moving back, bring the throttle to neutral to eliminate the prop wash. Don't throw the rudder over, it'll just stop the boat. With the big rudder on the very back of the boat, small movements will really turn the boat.
Please don't go with a three blade prop!
