you were at 3" first time,then 2-1/2" and now your at 3-1/2"aND YOUR HOLE SHOT MIGHT BE THE 4 TH BOLT HOLE,INSTEAD OF THE 3 RD.

I still like the 2-3/4" area...if your trimmed right and your throwing rooster tail that high,you need to come back down?If your at WOT. lol. the higher you go the higher the rooster tail and less pushing of the boat, you'll just be throwing all the water up in the air? lol.
AND you said you lost water pressure at 2-1/2" and speed. You sure you know where your setting at> j/k.
good luck