Based on what we heard of what the Garleans are doing to the occupied Ala Mhigans I doubt there are many Ala Mhigans that like their Garlean oppressors.

The Domans would not have rebelled if the Garleans treated them nicely and/or as equals. And we know Garleans are trying very hard to be the new Allagans and we all know how the Allagans were.

There's always a "good faction" amongst these type of Empires, but for the most part they seem set to rule over everyone.