I have driven and skied behind the 200 and the 343 just doesn't have the beans to push the surface area of the 200. I'm with Deke on this one, prop and recalibration will help but I can't see it making the kind of difference you need. The boat runs 36 mph at 4000 rpm, reducing pitch is just going to push the rpm's up to increase acceleration and I don't see that there is that much on the top end to work with.
Any updates? This boat needs to come with the 409 standard.