you need to ride more boards . . . . .
The shape and buoyancy are what make a board go faster. Fins also make a difference and quad fin or twin fin set up will offer more speed on a surf style board because there is no fin down the middle like a thruster that holds it back a little.
Flyboy (Jeff & James Walker) do a ton of prototyping of boards. Sometimes technical, but always entertaining read:
While these were written specific to traditional surfboards, the terminology is basically the same for wakesurfers: