Carbon and Kevlar are very different. They each have their strengths.

Kevlar

Lightest
Great impact resistance
Excellent strength is tension
Poor strength in compression
Absolutely sucks for finishing. It does not sand clean, it's fuzzy like an old sweater
Best in cored construction.

Carbon

Excellent strength
Easy to finish
Problems with sharp impacts and crack propogation
Stiffer
Current studies say it will last longer before it starts flexing, if it's prepreg. Hand laminates are about the same. Infusion should be almost as good as prepreg, I have some doubts.
Best as solid carbon, because the preregs are so good.

My personal favorite is 60-80% carbon with 40-20% kevlar near the middle. Once the limits are exceeded, it bends before it breaks and holds togather after it cracks.

I would suggest you try an A without a spinnaker first. They are fast in light air.