The problem with anything related to employees is that they make for bad cube metadata: flat, changing often, potentially with thousands of members. So, ideally, you want to keep them somewhere else, like a dedicated relational table, and then blend them with cube data only when strictly required. You could link their data via Attributes and do some Stage blending on reports.
A similar approach you could use is to keep them and all their data out of the cube altogether, by pushing it through BiBlend when you need to aggregate it.
