If you can find one, a Supra Launch d-drive. Deep sideways and freeboard. Might sacrifice some on the slalom side but the wakeboard wake will be good. You won't find them new though, they quit making the d-drive version for 2007.
TEST DRIVE & RIDE!!!! That way you know how each boat will handle & perform. I would suggest the Supra Launch 21, it nice and deep and takes rough water well. Itís also a great cross over boat with the hydraulic wake plate and gravity ballast for ski & wakeboard.
I think depending on how rough the water is most DD's are gonna ride a tad bit harder than V-drives because of the way they However I have been is some pretty hard riding SAN's. I think its mostley how the SAN's were driven at one constant speed. Bam Bam Bam across the water. I have a DD nautique and if you drive it correctley (vary the speed with the rollers) you can make a pretty smooth ride in rough water. I would bet that most DD's or V drives are all the same. They all have sweet spots in the Hull or V that they ride the smoothest at in rough water. Depending on how the boat is weighted will change the ride at a sertan MPH. You put any boat on the flatest part of the hull and its gonna ride rough. If your asking what boat can you put at 34 mph and leave it and drive across a rough body of water and will have the smmothest ride thats a question that I dont know or can answer.