Transactional replication subscriber vs AG secondary replica for reporting

I am trying to recommend my client a SQL server upgrade (from 2005-> 2014) which will allow the users to create record snapshot (via SSRS) from a read-only data source. Data latency should be kept to a minimum.

My understanding for transactional replication is a subscriber database schema can be a subset of the publisher, and can have different indexes; but I don't think an AG secondary replica can have a different schema from primary, even though a secondary replica can have different indexes?

I am also thinking about having the SSRS Report DB/ReportTempDB and operate independently rather than get replicated/synchronized. I think it is OK to have the secondary replica/subscriber to communicate to the SSRS Report DB/ReportTempDB via SSRS, right?

Note that for my client the DR is NOT a main concern.