Pete,
Just a suggestion about your perimeter bench seating. Check out the supersize pull-out awnings being used at the waterside end of Simon Beer Complex. They roll out and secure in less than 5 minutes and they seem to stand up to a pretty stiff breeze.
I don't think you will ever be able to shelter the row of benches looking straight down to the water but the row of benches next to the roof pillars could be sheltered from both sun and rain.
Also, for old geezers like me, a stack of "bench pads", fabric covered foam rubber, available on request, would triple the time my old bones could tolerate a bench seat!!!
I know you are in hock up to your eyeballs BUT someday, putting a boat landing and stairs on the North side of your premises would open up the possibility of offering a speedboat service for joy rides or island hopping where you DIDN"T have to deal with those beach pirates just up the road. Imagine a group of 2 or 3 guys and their TGs being able to gather at the PBG about noon, have a drink or lunch, pay YOU an honest fare for a boat, lunch and drinks. The group would be returned to your landing ready to party on!
Its easy to make suggestions when it's not your money being spent
Best Wishes,
Ronno