I would get a true HBA to replace the SATA expansion card. No USB enclosures. If you need to connect to external, do it with SAS connections and the HBA. You will want to chose a model that has both internal and external SAS.
What’s all the noise about HBA’s, and why can’t I use a RAID controller?
Multiply your problems with SATA Port Multipliers and cheap SATA controllers
