Autoincrementing indexes

I was wondering if Ignition does any indexing internally that would become an issue in a scenario where the databases are configured for replication.

For example, if I changed DB1 to work on increments on the pattern 1, 11, 21, 31, etc and DB2 to work on increments of 2, 12, 22, 32, etc would there be any issues?

No, the only way we would use the index is for finding the first or last row. We mostly use timestamps in our queries.