This is a rhetorical question in the sense that I don't really expect a clear answer. I have a Starboard Drive which I love. Love? Well. Maybe.I have surfed on it for years now and it does all the stuff you want. Easy to paddle, stable, can do re-entries, floaters, some nose riding though it is a bit unstable on the tip, cut backs etc. Good all around board except for one thing I hate. It is too corky. Hit the white water and you go pearling. I accept that that is a part of SUP surfing but here is my question. Could you add a weight like ballast to the under side of a board that would overcome the corkyness? Please don't write in and advocate another board. It is a basic question.
My guess is no.
I think the main problem is the rails being too thick, not so much the volume.
Adding weight will just make it harder to turn and slower to paddle.
But I haven't had anything to do with sups, although I've been making boards of one sort or another since 1961.
I've found thin sharp rails at the tail and medium eggy rails in the centre work well.
A lot of Sups I've seen have rails too rounded and too thick at the tail IMHO.
Ummm... Not being funny but there is a SUP forum.
Well I wouldn't have seen it if it was posted there.