I did a rather crappy job on the hull interior, earning myself a lot of extra work.
It seems that, after building four kayaks, and having the same problems each time, I finally had a revelation about saturating the glass. I had usually been using too much epoxy in one place at a time, and letting it saturate too long. The fiberglass wants to float off the wood, of course unevenly, causing ripples. This time, I let it saturate a minimal length of time, and removed the excess thoroughly and immediately. I maintained a "wet edge', as with painting. Voila! Only one or two small ripples! The fill coats went well-nearly filled the weave on the second coat, in some areas.