Mainly for active-active disaster recovery purposes, there should be an SPM election policy that automatically chooses a host with higher SPM priority when it comes back up. This is needed for active-active DR scenarios since there can be situations when a host, that is located in the backup remote site and usually has higher latency and low bandwidth to the main site's storages, is elected as the SPM (for example, when the main site's hosts are in maintenance for upgrade). Of course, this auto SPM select should be done with time-frequency limitations to prevent SPM election storms.
Frankly, I don't think this is the right way to go. You can have all sorts of bad situations where a host comes up on one side of the cluster but the storage hasn't flipped over, etc. IMHO, the way to go about this is to have something external (possibly even the admin himself/herself manually try to force the SPM back to the "right" side once he/she is convinced it's operational again.
I prefer we wait to see if a customer requests something like this. Closing for now.