The old transom designs and large splashwells are a waste of space only with respect to less floor space, but...................
A boat still needs a place to have a bettery or 2 as well as the fuel tank, which in the case of the older SS models, are under the large splashwell. In addition, trim motors/pumps also make there home there.
Aft decks nowadays are the result of in-floor fuel tanks in the main cockpit area allowing for smaller splashwells. The lateral strength is better these days because the port and star gunwales are connected also by the increased decking.
On my SS project, I look at my wasted space as storage for my permanent fuel tank and trim motor. They just don't have top access, so instead, I modified the aft with side access and removable panels.
The raised deck I made created storage for battery and general gear. I figured that the back main deck behind the passenger seats had no purpose except to either land a fish or general entry into the boat, hence the raised deck below......................
Need to add the face wall which includes a recessed LED 18 in white, then the top trim bar on the rail mentioned which will harbor 2 Scotty triple mounts for trolling.
The raised deck sets the fishermans butt seat at 25" total height on a pedestal for casting. The raised floor(12") also makes it easier to reach back to the transom area, easier to get into the boat, and provides new storage, in my opinion. The wall can be removed if needed with 6 bolts and a few L brackets in the new storage area.
I guess my question would be....................is it worth doing the modification of moving the splashwell support bar to gain 6" of floor space? In my opinion, an SS and runabout fun is really about the large bowrider area and not the aft area.