Depends on the purpose of the rifle. Trying to drop weight for a walking rifle? Go carbon with a light weight chassis.
Wanting short for maneuverability but need weight for stability and not going to walk around with it? Go thick.
I have had carbon, medium palma and a friend has a MTU all 16”. The carbon was for a walking gun, and the 2 heavier contours were built for prarie dog shooting out of trucks and off tripods where the extra weight helps stabilized for shooting the little furry suckers at distance.