I'm no pro but you need to stop pulling in on the rope. Focus on keeping your arms straight through the wakes, pulling in on the rope is causing you to lose your leverage position and speed as you cross the wakes. I think this is also causing the wobbles out near the buoy line.
you should be hanging your entire body off the handle as you are crossing the wake with your elbows pinned against your chest. Something that has been helping me get into a more stacked position on my offside is thinking about pointing my sternum at the tree tops while keeping a balanced stance on the ski.