You should be fine. You decked your's about 2" higher (by looking at your 2x2's across the top of the benches..) than mine. I decked almost even to the tops of the benches and I didn't have any problems. When I got into lakes that allowed motors, I just sat down when the wake started coming to me and I was fine.
My wife went with me a few times and we both stood - and I could set the hook with her standing and she didn't move. It was a little wobbly, but you get used to it. Just get your partner to sit down before you set the hook - or atleast warn them before you do it or they might go over!