Hi Scott,
I was impressed with the work you've done so far. Lots of creative thinking. A very interesting stacking use of your in ground pool. We learn by observing as we go along, so there are no mistakes, really. If you're interested in ducks, I recommend Jack Spirko's excellent videos, "The Duck Chronicles" - season two, on YouTube. I also got turned on to Jake Mace via John Kohler. I consider myself to be exceptionally fortunate to be taking Geoff Lawton's PDC right now. Good luck with your garden. Maybe you could plant some edible ground cover around those new fruit trees?