Time to head south for vacation!
Anyway. One thing that caught my eye before is location of your self bailer.
Logically I would place its bottom edge at least inline with floor otherwise you boat will have standing water after getting swamped since not all of it will drain out. That's the way my F470 is (Let alone there is one below floor) It's inline.
Of few pictures I could find on net.
2005 Avon W465 | Boats & Yachts for sale | Used Boats and New Boats for sale
Bailer opening appears more or less inline to floor.
If that rear retainer is too low floor will be out of parallel with tube's axis. I think that could cause tubes to take inverted hook sorta banana shape as they conform to rigid stringers. As result engine might be running too high in relation to keel line hence cavitation/ventilation or I suppose result maybe unpredictable. Maybe front will come down a bit since front panels don't have any rigid stringers connecting them.
I would lay a board across tubes and measure distance to floor at different points. See if they are parallel. And/or flip boat over to check for straightness.
Ask defender to send you picture of another work boat. Amazingly hard to find this stuff.