Now that I've done all the puzzles there is nothing for my Builders to do except inspect huts and fix huts; I hate to make them do it but it would be hard to get Esteemed Elder without Master Builder status. Wish they had something new to build.
Farming and Research are pretty easy to get Masters in, but what do people use for the other one? My Adept Doctors never seem to get to Master before they die, and surely there could be at most one Master Parent considering the population limit.