Hello migrace,
I'm with you...ultralight flying should be for economical fun only.
My Hiperlight, with a Rotax 277 motor,was originally FAR part 103 compliant.Inits present configuration though, witha Rotax 377, it weighs 131kg (288lbs) empty.
95.10 doesn't prevent you from building an aircraft to FAR 103 standards. I'll be watching to see what you produce with genuine interest.
Bruce