I am in a semi-similar boat. Currently using the Citi Premier / Forward combo (in lieu of CSP/Freedom combo) that is semi decent for food/entertainment and redeeming the TY points for flights with that extra 33% one gets from having a Premier.

And was thinking of getting either an SPG or CSP (or both replacing my citi cards) but was wondering how would I accumulate enough points (in the non citi bonus categories) to make it beneficial. If I buy a flight using TY points, can I upgrade to a better class/seat using airlines points that I xfer from either an SPG or CSP?