Having reviewed and owned the VR4SR MkII for a while, I suggest that you move to a more sizable speaker, one which is physically larger and with more prodigious bass drivers. You will only get so much presence from the VR4Jr - this is not a sleight to the speaker, it would be true of any such speaker.
To get a more commanding performance you will need a larger speaker. I suggest you consider one of my longer term favorites, the Wilson Maxx 3 (not sure what you could get it for used, but worth a look), the legacy Whisper (I reviewed and own the custom DSW version I wrote up for Dagogo.com) or Aeris, or consider a prodigious panel such as Sound Lab or Kingsound King III (also reviewed and own). The panel might be a winning idea, as you have good subwoofer action now, and the panel will throw a huge soundstage. If you are not so concerned about dispersion for off axis listening, then I would suggest you seriously consider that option. I think the panels could sound fabulous in such a room. :)
My one concern regarding panels is that you seem to drive the speakers pretty hard. My colleague, Larry Borden, felt the King III couldn't be driven to such high levels as the Sanders hybrid ESL, but I've never had an issue where the King III isn't satisfying at pretty high SPL. But, I don't attempt to make myself go deaf when listening, either. :) You would want to get a second subwoofer if you go that route. You may not even need to listen at the same SPL level with big panels to enjoy the experience more.
Perhaps you should also consider Montana speakers by PBN, and you could probably find a biggie used as well. I would avoid any speaker 4' and under if your goal is to fill the space well and get a prodigious SPL experience. There is no replacing proper sized drivers when that is a primary goal; the nature of the low end is fundamentally different in experience than through an array of smaller bass drivers.
I do not wish to debate my suggestions; I'm simply offering my experiences.
One more thought; if you are currently passively biwiring I suggest you use the "vertical" biwiring method, keeping one amp per speaker, versus the "horizontal" method of splitting the amps' use between speakers. I find the vertical to be a bit better.
To get a more commanding performance you will need a larger speaker. I suggest you consider one of my longer term favorites, the Wilson Maxx 3 (not sure what you could get it for used, but worth a look), the legacy Whisper (I reviewed and own the custom DSW version I wrote up for Dagogo.com) or Aeris, or consider a prodigious panel such as Sound Lab or Kingsound King III (also reviewed and own). The panel might be a winning idea, as you have good subwoofer action now, and the panel will throw a huge soundstage. If you are not so concerned about dispersion for off axis listening, then I would suggest you seriously consider that option. I think the panels could sound fabulous in such a room. :)
My one concern regarding panels is that you seem to drive the speakers pretty hard. My colleague, Larry Borden, felt the King III couldn't be driven to such high levels as the Sanders hybrid ESL, but I've never had an issue where the King III isn't satisfying at pretty high SPL. But, I don't attempt to make myself go deaf when listening, either. :) You would want to get a second subwoofer if you go that route. You may not even need to listen at the same SPL level with big panels to enjoy the experience more.
Perhaps you should also consider Montana speakers by PBN, and you could probably find a biggie used as well. I would avoid any speaker 4' and under if your goal is to fill the space well and get a prodigious SPL experience. There is no replacing proper sized drivers when that is a primary goal; the nature of the low end is fundamentally different in experience than through an array of smaller bass drivers.
I do not wish to debate my suggestions; I'm simply offering my experiences.
One more thought; if you are currently passively biwiring I suggest you use the "vertical" biwiring method, keeping one amp per speaker, versus the "horizontal" method of splitting the amps' use between speakers. I find the vertical to be a bit better.