Traffic that heads through vCenter in a WAN vSphere architecture:
- vUM patches
- Template Clones (that live in one location that you are deploying in another)
- virtual console
- linking virtual CDs
Some tips with syncing options listed here: Drink Me
While PHD's free patch downloader can help with lack of local vUM.
Other than connecting locally to the ESX(i) server that is hosting the VM, I don't see another way around virtual console access.
I'll update if I come across anything else.