Today I got both Jack and the elf primed, and Jack attached to his flat base. They don't look terribly different, but next time they should be ready for paint.
I used the airbrush to prime both of these. I learned something priming the elf: If you're going to airbrush prime with this kind of base, prime the base and figure separately. The natural materials on the base suck up primer, and it seems like you need to be generous with it. That is not the case for the figure. As a result, her legs and boots have a heavier coat of primer than they need. I don't think I lost any detail, but it's not the best. Also, I got rough spots on the plastic base where I was holding it while priming that I'll probably want to clean up.
Jack was primed pretty smoothly, I think. I haven't noticed any problems yet, anyway. Then I glued him on to the base.
Now I'm just wondering why so many figures have their heads tilted down. :p