Hi,
hm... I'm not aware of any other "hard" limits then...
Did you already set up a 3-node Management Cluster or are you running a single Manager setup? I remember it was a limit in NSX-V that a single manager only can manage a single vCenter, although this limit seems not to be present on the configmax website.
There could also be a difference when using the UI directly served by the manager and not via the vSphere plugin.