I'm also into planes, and about to make a machine... and it'll have glass all over it.
Carbon and Kevlar are stronger, but multiples of the price. We're not building a plane, so weight isn't quite the premium... so... with a wodden substructure, and a glass shell... methinks it'll be generally improved for the effort that goes into it. I'm also going to laminate thinner plywood pieces either side of glass and then glass the exterior... it should make the whole thing very stable to things like moisture or whatever.
...anyways, fiberglass? yes, have some!