I think there is a perfect mix for the conditions.
Flat wetted area should be faster .
Longer wet area slower, but a board will lift to the wetted area thats equal to the speed.
I hear a shorter wider wet area is faster , ( cutouts ), but speed boards are long and narrow.
A longer front rocker will increase wetted length but also slam less into chop.
I have a slalom board which is very short and wide and almost no rear rocker and not much at the front either . i suppose its built like this for good riders to adjust to the pitch of the water over rough conditions . And be able to turn . Way above my skills , And a good racers board doesn't really touch the water that much , flying on the fin in the face of danger overpowered.
I would think each board combo works different , so many variants and what you think might be faster , may not be.
So to answer your question...dunno