High efficiency speakers for Shindo

I recently bought a Shindo Aurieges pre and think that a total revamp of my system is now in order. After doing some research it seems that the best match for the pre is, surprise, surprise a Shindo tube amp. Since I'm on a budget, the entry level Montille is most realistic, its a flea powered 15 wpc push pull. I'm thinking that this won't do with my Gershman Avant Garde's which are a rather inefficient 87 dB, so I may have to trade em in.

But I do love the Gershmans for their great bass response and silky mids. Can anyone suggest a high eff speakers (say 90+ dB) that would mate well with the Shindos and also give me good bass slam so that I won't regret selling the Gershmans. My basement room measures about 13' x 20' but with a 6' ceiling. I listen to a huge range of music - classical chamber music, jazz, indie rock, electronic, everything from Albeniz to Zappa.

Speakers that I've been considering are Audio Note, Living Voice, Ref 3A. Others have suggested single driver speakers like the Omega which are intriguing, but can they really rock out? I'd like to keep it below $5K used. Any other suggestions or thoughts on what would be a good fit?