MCSE is heavier on the actual server side of things, so .. active directory, GPO, DNS, forests and domains, etc. Are you the 'head' sysadmin or is there someone above you .. i.e. do you really need to know the details of AD and how the GPO flows down, how DNS does and doesn't forward, etc? It seems like a combination of MCSA and MCITP might work best for you. Which of the two job functions do you do more of?
http://www.microsoft.com/learning/mcp/certifications.mspx