There are a couple of things I would look at for materials.

1) I would look at a mixture of carbon and kevlar. Kevlar has poor compression strength and carbon has poor resistance to sharp impacts. Alternating layers of kevlar and carbon, seem to work better that a single fabric that has carbon and kevlar in the weave (TWAIN). My favorite layup is 2 layers carbon/ 1 layer kevlar 49.

2) I would look at using phenolic rather than epoxy. Phenolic is heavy but very durable. I would not use it to build a boat out of it but I would use it for the trailer cradles or something to drag around on the beach. Autoclaved Phenolic fiberglass is very tough stuff


I also have a question, are the braces intended to flex ? If the braces need to flex, you might have a hard time building something better. If they don't need to flex or don't need to flex as much, carbon might be a better answer.