Haven't made anything, but tried this with a 12'6" Fanatic

It tried to beat up the boat pretty severely.
So tried this.

Effective, but limits access a bit.
Haven't done it yet, but an inflatable would be much better.
Would be fine tied to the boat, and could be strapped to lifelines down the side without damaging board or boat.
Could even strap it to the outside.
Just looked at your photos, and lifelines don't seem to feature - maybe a couple of staunchins to mount it to?