Currently the "local" eventHandler works on 'objects' only.
The EH does not work on groups. In case of ownership transfer from the server to a HC, unit/group directives are lost. E.g. when a group has been garrisoned (each unit in a seperate building), the group units lose their position data and regroup on their leader after group ownership transfer.
Currently I am solving this by storing the unit's data + position data in tn array and setVariable @ group. Before transfer a loadbalancer script running on the server retrieves the data and then then remoteExec's the data to the new owner (HC). New owner then executes a function to re-apply the position data. Works well, but it is a costly method. Especially as garrison scripts are quite costly as well.
If an EH can be applied to a group than the script that applied the group directives (e.g. garrison) can also apply the EH and re-apply the group directives after transfer.
The EH won't have to change that much. Instead of returning (_this select 0) the object it returns the group.
A lot of (larger) communities use one or more HC's. The EH would make life a lot easier for mission makers :)