this comes up a lot, I'm sure they will come up with something for this eventually.
Yeah, hopefully. The ability to migrate from one place to another would be great, especially if it left everything we built in its place, so that the game world would always be different even after tribes moved on. Of course, it should be something you can't do quickly or easily so that it can't be exploited for a number of other reasons.
Agreed... maybe something that can be worked on in a leadership tree. Definitely should have an obnoxious cool-down though. Once a season sounds about right. I see where this can be used in a negative manner for those few who like to cause drama though. Wreck a territory, move on, wreck more.