Just my opinion, but your system is at the level where true upgrades are really expensive. That's not to say that good equipment can't be found at a decent price that sounds DIFFERENT (only you can determine if different is an improvement), but true upgrades get really expensive from where you are. Given the inability to separate HT from 2-channel right now, if it were up to me, I'd leave your very nice system alone and focus on the room. Get that &@*%!$ TV out from between your speakers or at least a few feet behind them. Spend some serious time with a test disc and sound meter if you haven't already, and make sure you have optimal speaker and listening position placement. Then take a look into what room treatments might benefit your room. You might be amazed at the improvements you can make for very little money.
As far as system changes go, I agree with the second sub addition, but I stay away from subs that don't take line level inputs (that's just me, others disagree). No subs or stereo subs when it comes to two-channel listening...I've never liked a single sub for two-channel. That's why I use three subs in my system...one right channel, one left channel (for use in 2-channel and HT/surround) and the third connected to LFE (for HT/surround only). The right and left channel subs are set to blend with my main speakers while the LFE sub is set to shake the floor and rattle the walls when appropriate during movies.
Hope that helps--->E
As far as system changes go, I agree with the second sub addition, but I stay away from subs that don't take line level inputs (that's just me, others disagree). No subs or stereo subs when it comes to two-channel listening...I've never liked a single sub for two-channel. That's why I use three subs in my system...one right channel, one left channel (for use in 2-channel and HT/surround) and the third connected to LFE (for HT/surround only). The right and left channel subs are set to blend with my main speakers while the LFE sub is set to shake the floor and rattle the walls when appropriate during movies.
Hope that helps--->E