Delete BWA indexes is automatically done during post upgrade processing.
Obviously you need to check contracts with hardware vendor (especially if you are switching to a different one). That's also where you should ask about data center integration of the new hardware/network and high availability/desaster tollerance/backup & recovery which are all a bit different for HANA vs. BWA.
And you could ask yourself if you move your systems to the SAP HANA cloud.
Regards,
Marc
SAP Strategic Customer Engagements (SCE)