I also have health concerns with urethane coatigs.

Anyone here tried KlassKote? Looks to be about the same as Hobbypoxy or Superpoxy. Had good results with those back in the 80's and 90's. Then they were phased out because of EPA regulations, I believe, so I'm wondering is KlassKote is really the same.
Will it hold up to 30% nitro?

Actually, what about using butyrate (sp) dope. It is supposed to be light. Never used it on a pattern plane but it used to hold up to C/L stunt planes years ago but nitro percentage was minimal (5%?) way back then (don't ask).

Or a combination of epoxy primer and dope top coat?

Bob