I free ski behind a 1980 Galaxy that's about 21 feet long. It weighs 3500 pounds. Needless to say, it's a big boat with an even bigger wake! I always ski at 15 or 22 off. The wake is a little softer there. If the line is longer, the wake is too wide. If it's shorter, there is a steep ridge from the deep V hull. I tried 35 off behind it for fun but couldn't do anything due to the ski almost getting ripped off my feet at the wakes. Trim seems to make only a small difference - the white foam area of the wake gets wider but not much shorter. Speed doesn't change the wake much from (30-36 MPH). Hope this helps if the boats are similar at all (ours has an I/O too). The deep V almost makes it impossible (I weigh 145 - it's easier for my dad who is substantially heavier).
As far as style, bend your front knee over your ankle (which is normal I think) and bring your hips up to the handle. If you stay back like this (with "soft" bent knees), you should pop right through (with only a little air that becomes normal). Of course, if you lose form, you will crash hard (I've had quite a few OTF).
Like I said, this will only help if our boats are similar (and most I/O boats have pretty similar wakes).
Or you could just buy a racing boat. I saw someone skiing behind a race boat the other day and there was maybe 3 inches of wake!