Speaker Recommendation for Nuforce Cary Blend

I am thinking of upgrading my speakers, as they have fallen behind everything in my system and sound a little muddled with very fast music (Kings of Leon, some Pink Floyd). They sound great with slower paced music but just sound confused sometimes.

Current setup

Cary 306 SACD Pro - Sweet upgrade from 303/300
Cary SLP03 Preamp - Verdict is still out, might need to retube.
Nuforce 9v2se - about to upgrade to v3se but highly recommended.
+ Sonus, Nordost Speaker wire, Mac Cables XLR

Speakers Dali Mentor 5

Any thoughts, I tried MS5 Euphonia but they were just to big for my room. Thinking maybe of trying out Wilson Sophia 2's, something that it isn't to large ($6~$11k). In the early 90's I liked the Tannoy / Arcam blend, english sound but haven't been impressed with Tannoy as much these days.
One more thing, which might go against the wilson's. I do listen to a lot of music at low volumes.
Try to Paradigm Signature S2 or the small Harbeth's, those would both sound stellar. Either of those would allow you to upgrade you preamp to a Cary SLP98P or ARC LS26, and get a vinyl rig.

Love the NuForce, very nice, the Paradigm Sig's are a sick value.