In order to eliminate as much additional finishing as possible on the cast part, as well as to aid in the mold creation, I decided I should smooth out the ridges that were created as a result of using multiple layers building the form.
Using wood filler, I filled in the transitions between layers and also some gaps left during the initial glue up.
After drying, it was sanded smooth and shellacked. The form, not me.... (Okay, I probably was a little shellacked at the time too.)
Hopefully, this will make forming the mold much easier as well as prevent a lot of finish work on the casting.