I started working on a full figure and noticed the active points were a little over 5.1 million. Is this ok or is there a safe zone I should stay in?
Also why is it when I’m sculpting onto the face the brush marks are the lowest subdivide?
The number of points/polys you can handle depends upon your system specs. But 5 million polygons is ok for most computers.
Your other question has to do with a feature that ZBrush has which reduces subdivision levels when interacting with a high resolution model so that it can continue to operate in real-time. What you do still applies to the highest level, but ZBrush renders a lower level. When you stop interacting with the mesh, it gets rendered at the full resolution again. This feature is called QTransThreshold and you can change its setting in Preferences>Performance. The default value is 1 million polygons, so anything higher than that will render a lower level while interacting. Increasing the value will adjust the effect, but can also sacrifice performance. You may need to hide parts of the model and/or move the cursor more slowly to compensate.