Just want to add- carbon fiber is stiff, but has virtually no abrasion resistance. Putting a bit of glass over it is a very good idea, even if it's 2-oz.

I have found the same- that it is hard to tell when it is wet out, and hard to make the look consistent. The greatest success I have had is by adding my fill coats without sanding between- at most scuff between coats with scotchbrite if I miss the "no sand" recoat window. That way you can tell when you're getting close. I can't say for sure in your case- but in my experience on small areas, the 3D effect is lessened when you sand into the fibers.

If you speak with the tech engineers at West they will likely give the advice that unless you are vacuum bagging s-glass probably ends up with a better strength-to-weight ratio because it is very difficult to control the amount of resin in the CF. For a small kid's kayak it's inconsequential, but if you're building a racing kayak and after the minimum weight it's hard to do with CF without vacuum bagging.

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