I agree, avoiding pits in the first place is desirable :-)
Lowering the viscosity sounds good. Didn't really have this problem with poly-ester resin.
Guess I didn't use enough resin to begin with?
I am using West Systems Epoxy 105 with special clear hardener. I made a mold of a motorcycle chain guard and vacuum baggeda carbon part. The molded surface of the part is not SMOOTH. I tried sanding it a little and brushing more resin on to fill voids but the resin resists voids like the plague...