Hi John,
Sorry if I missed your additional clarification and getting back late. About the input buffer for single supply operation and gain > 1, the RFBL should be terminate into ground. If you want to offset your input signal to VCC/2, then you should just remove the R6 so that the IBUFIN+ pin is bias to VCC/2. Does this make things clear?
For the ac coupling capacitor, you may want to read this FAQ: http://ez.analog.com/docs/DOC-1420
Thanks and best regards,
Emman