I put midship cleats on a 323. I used the Forespar folding cleats that clamp to the toe rail.
I opted for those simply because the flip down and cause less of a trip hazard on the side deck.
Furthermore, I did not have to drill additional holes in the deck, nor find a way to get backing plates above the headliner. Any load on the cleats is spread out along the toe rail.
The idea started out as a temporary solution, and that was about 14 years ago. Still haven’t changed to a more permanent installation. The 323 is a light enough boat that it does not put a lot of strain on the cleats from the spring lines.