Well, for me, I promised the wife a beach house. I may not have mentioned "floating." So my plan is to get her really drunk and smuggle her on the boat. I figure on a stable cat, and with a household toilet, it might be a couple of days before she figures out she's on a boat, and by then she'll be sold.
More seriously, we all agree with KISS. Which is simpler, a household toilet or a marine toilet? I
...but there are a lot of toilet problem threads. And nothing will spoil your day like working on the working end of a toilet.
With that as starting point.... got it.
My view is that neither is simpler, assuming you include the whole household SYSTEM that Peggie mentions; they're just different.
IOW, if you include freshwater source, freshwater path/routing, waste water destination, wastewater path/routing... as well as the way each toilet design works... the two approaches just get there differently. And one of 'em has a whole municipal treatment plant involved (or maybe an in-ground septic tank).
As to toilet-problem threads... yeah... but if you sort those into piles... and ages... you often find that Bubba is working with a 20-year old manual pump saltwater toilet... and of course old things sometimes need more maintenance than the newest product on the block.
Complicated maybe by installation design issues: Is gravity helping anywhere in Bubba's waste line? Did the installer use good, modern sanitation hose?
Complicated further by the way Bubba (and Bubbette, and guests) use the thing: Did they actually flush enough water to clear waste lines? If the thread is about clogging, did a guest try to flush a whole roll of paper towels? Or if the thread is about odor, has Bubba used any of the appropriate methods and treatments (see Peggie's book).
And even further by Bubba's wallet -- or proclivity to open said wallet from time to time, at least long enough to let a moth escape. Did Bubba maintain the system? Did he use maker's replacement parts? Or chewing gum?
And so forth.
-Chris