JCE 2 now uses profiles which is a permission system. Goto Components > JCE 2 > Profiles , Select and Edit or create new profile.
For test edit default profile and add your username to understand its system. Then you can create a profile for your users , profile for your editors and profile for your admins.
Each profile allows how much or what settings are available to a user during editor window.
Short links to JCE Profiles
administrator/index.php?option=com_jce&view=profiles
administrator/index.php?option=com_jce&view=profiles&task=edit&cid[]=1
See you around...