Here is some of my process for sculpting a default shape from a posed smile in ZBrush.
Basically i had previously sculpted an original concept face in a smile pose, but now i want to make a default pose for the face so i can proceed with facial deformations, improving topology etc. So here's are some tips that may be helpful. Also not at the end i was able to use ZBrush polygroups as a way to select Maya vertices by uving the polygroup islands in ZBrush (uv master plugin) then using Goz to export the data into Maya.
The main take aways of this tip are:
1. can use ZBrush polygroups to help sculpt default shape or even blendshapes.
2. Isolating polygroup (making just 1 polygroup visible in view) is an incredible tool that will make it so can focus on one area of sculpt while not affecting others.
3. ZBrush uvmaster tool is amazing to be able to use those polygroups in Maya, the polygroups can be used to make quick vertex selections for facial deformations.