Response from Cisco TAC:
++FEX support for both 2348UPQ and the 2348TQ switches with 9500 switch is there in 7.0(3)I2(1) release.
++N7700 and N7000 are very feature rich compare to N9k. N77k & N7k support 64 FEX. N9k support 32 FEX support as of now. Increase of FEX support in N9k is not there in road-map. If its having very huge business impact then you can contact Cisco Accounts Team they will talk to BU to include this feature in their Road-map.
