A couple of questions:

Going to BOM R/T in company paid business class.

Outbound:

SEA - BOM I can choose either DL via SEA - JFK - BOM or CO via SEA - EWR - JFK, will collect Skymiles regardless. Any signficant reason to choose one over the other i.e. DL 777 BE vs CO 772 BF on this route?

Returning, the optimum routing is on KE BOM (A332) - ICN (B772) - SEA

The return routing is available at the same price either as a DL codeshare on KE or directly on KE. Again I will be accumulating Skymiles regardless. Any significant difference between ticketing as a DL codeshare or KE on this return routing?

Thanks in advance for your input.