I have beat the crap out of my Sea Nymph. Still doesn't leak a drop. The older two strokes run forever. Mine's been in the shop twice in 21 years, once packed full of silt from chasing a crippled duck into no man's land, the other to replace a fitting and tune the carb.
Get enough motor. You can run bags to slow down but you can't do much to speed up.
I love my 14 but for what you listed a 16 would be better.