I too am from Alberta, High Level to be exact, and owned all the same toys as you. It's very hard to get the same thrill on water from a standup jetski as you can on snow or dirt just because of the physics of it. It is a different thrill and requires a bit of an adjustment. There is a point where you can have too much power but thats a pretty decent point in skis and just about anyone can handle a ported up 701 or 760. Knowing where you are coming from, I would start with a well ported 771cc 61X at an absolute minimum and know you would have the hang of an SS900 in no time. The power will actually help you learn and pull out of falls.
Hulls are a different story altogether. I had an SXR and a SJ up north and rode the one that best suited the mood of the day. I'd rip a bouy course for a tank and then swap over and do freestyle for the remainder of the day. The last few years the Seadoo was only ever used to put up, adjust or take down the bouy course and was stuck on the trailer the rest of the time.
Try and ride a couple hulls and get the feel for what you like before buying. Until then, any decision is purely based on others opinion and preferences and means nothing. Don't rule out catching a plane to one of the freerides either. It would be the best way to test ride a bunch of different skis and see what's out there for you and may save you some time and money as well as meet a great group of guys and make some new friends.
P.S. Molson Canadian is a huge hit at the freerides so stuff your suitcase with as much as you can carry.