If you are having a porpoising issue even with a Diverter, the Straight snoot is the shiznit. Do you know what loader you have?
What causes a porpoise is the lack of available thrust to sustain the attempted lift. In other words, as the hull begins to lift from the water, it becomes "heavier" and the thrust providing the lift is insufficient and allows the hull to come back down, then it has sufficient lift to begin the lift again, only to keep repeating until you change the angle of the nozzle or get on and /or off the loud pedal.
Ultimately what you need is a straight snoot to afford the pump a little more leverage on the hull and a ride plate to push off of. A full droop in my humble opinion can exacerbate the porpoising issue.
The ultimate fix would be about another 300 HP and a bottom detailing to remove any hull defects on the last 8' of the bottom. Not to mention moving as much weight rearward as you can reasonably do without being ridiculous about it... BTW, a light jet is a happy jet.

Good luck.
GT