I agree with what others have said - that tabs are still a pretty good idea for a boat that size and mounted correctly, you will not loose any speed.

As for what's causing the boat to twist coming off a wave, I'm not convinced it's prop torque. Heck, I've got a 27" pitch prop on a much lighter boat and it comes off a wave perfectly straight. More pitch and more rake should twist the heck out of mine.

As for using tabs to even it out, think about that one for a minute. That would mean one tab is down more than the other. When a boat lands, the stern digs in and the effect of the tabs is magnified. That would mean you'd take a pretty good roll to the other side. Not my idea of having fun.

My recommendation would be to add a set of tabs anyway, but do some sniffing around for rigging and balance issues that might be causing the twist.