Trying to refine the replica placement to be more uniform across multiple nodes if we have sufficient amount of live_nodes in Solr available,
1. When we have live_nodes in excess of the replication factor which existed during the time to backup we can do away with creating multiple replicas for same shard on the same live_node to ensure better distribution.
2. User should be given warning or, option to go ahead with the Restore API if the number of live_nodes is less that what the collection was originally created.
Details of the two issue in the attached PDF and initial patch attached with the ticket.