Set up a hot/cold water deck shower on the aft section of the deck.  One is the valve, and one is the actual nozzle.
With the swim platform going in, the shower will be right there for a nice shower.  The other valve is the salt water wash down.  So when we catch the big fish, or crabs, or shrimp in the dinghy, we can wash it all down.  Good to plan on messes.  I like to blame the kids, but I am the messiest.