May be off topic a bit:
Bryn,
Sorry - I exaggerated the thickness (lazy typer!) - it's more like 2.6". The deck is domes out at the edges so the rails are really fine (maybe 1" at 1" in at mid rail). At 23" it's of moderate width. There is a lot of area in the tail (18") and the outline is parallel behind midpoint. It was designed to cover ground fast, get to the lip fast and to travel out onto the flat and then come back fast and smooth.
I kind of overdid the fast at the cost of looseness.
http://i119.photobucket.com/albums/o155 ... ow_mod.jpg
(note this pic doesn't show the swallow tail)
It goes sensationally well in glassy conditions, is highly responsive and a pleasure to surf. But it's a handful in wind chop, with the rails catching the chop.
The outline of the board make it better in walled up, barrelly stuff. If it's sucking clean then the rail thickness feels great. Tube rides are totally controlled.
My thoughts:
Keep a bit the volume in the center line so you can catch waves. This board volume is ~40 liters - the same as all my boards regardless of length, so it paddles well.
Once you're up and riding then center line thickness has little effect. If you want to make it feel thinner, reduce the rail thickness. Overall I'm staying with slightly puffier rails (1.75" at 1" in at mid rail) because I think they handle average surf conditions better. And average surf is what I get most of the time. I'm hanging the board on the wall until I get to Indo again (or maybe the Gold Coast).
