Being new to Connected Management Groups I might have overlooked something. However, it seems that from connected management groups you can see alerts only? This mean, no connected group instances (like Windows server instances) and therefore also no state information.
For quality OpsMgr monitoring I believe you need both state and alerts. So, if my findings are correct, I consider the concept of connected management groups partly broken.
Yes, you are right, the amount of data is limited to alerts, discoveries and some otehr data types, but state information isn’t available. Direct management of a connected groups is also not posible.
I think it would be pretty hard to iplement management features for connected management groups, considering the fact how complex the whole thing is.
Still it it pretty usefull to have all that data in your console, don’t you think. You can react at least in the presence of certain alerts.