Sorry to be slow. If you are sticking with 2.1, it's really hard to call that theater. In my opinion, you really need an equal quality center channel speaker with a matching amp to your L&R speakers to get any quality listening. You will never get a good balance across the soundstage and will be adding extra electronics to the signal path.
I would push you to scrap the receiver and just go with a nice pre/pro and amp. With a good pre/pro you can add amps and speakers as you go. Something like and Anthem or Sunfire will have great DACs, nice bass control and will rival most 2 channel rigs while producing great theater results.
I would push you to scrap the receiver and just go with a nice pre/pro and amp. With a good pre/pro you can add amps and speakers as you go. Something like and Anthem or Sunfire will have great DACs, nice bass control and will rival most 2 channel rigs while producing great theater results.