Re the last point (that instances don't actually matter insofar as relocating is possible), I would respectufully disagree.
Instances don't matter *if* one does not use the local or federated timeline and one does not car which other instances federate or don't.
On any two instances, the local and federated timelines, *and* the home timeline, may differ greatly and thus, leave a very different impression to anyone looking at, and comparing, both.