Always been a shortboarder and came to supping because I love the difference in riding a wave. It's like having two lovers

Always take both down to the beach and have even supped and surfed the same break-it's a worthwhile thing to do for ***ts and giggles.
There's loads of difference between sup and shortboarding which is why we're so lucky to have both. My skills are much better on surfboard due to 40+years at it and the standout difference is barrels, getting tubed, pulling in, covered up and spat out.
For me I don't even try and surf a sup like a shortboard so there's no point comparing manouverability. I love the diversity of difference in manouvres between the crafts, that's the point.
I'm only recently into supsurfing and it's influenced me to have a crack at midlength shorties to add a bit of glide to that flow and yeah having a lot of fun. Also a good weapon for catching more waves when it's crowded or getting into them earlier if needs be. So change your fins, boards, location but if you can do both then go for it. For me it's a win/win I reckon