Thank you for those thoughts.
Does Neo4j perform well when creating large numbers of relationships between existing nodes? Let's say you want to create relationships in both directions between each Customer and their Orders. Would you suggest something like the expression below, or is there some better way to accomplish this, particularly when the number of Customers and Orders is very large?
MATCH (c:Customer), (o:Order {customerId: c.customerId})
CREATE (c)-[:HAS_ORDER]->(o),
CREATE (o)-[:ORDER_OF]->(c)