Best amp options for JM Reynaud Bliss Silver

Hi friends,

I have a nice pair of JM Reynaud Bliss Silver speakers, which are currently being driven by a vintage Audire Crescendo SS amp and a Linear Tube Audio MZ2 pre. 
My set up is in a pretty large loft room and though it sounds good, like a typical audiophile, I think it can sound better. 
 

The JMRs are 4 ohm and 89db efficient. 
Currently considering a Conrad Johnson Premier 11 (I really like tubes!) or maybe a First Watt F7 (I like class A sound too). Not sure if either of these would match the LTA pre’s input impedance better?

Hoping for better bass extension and improved soundstage holography. I do prefer a warmer more musical sound versus hyper detailed hifi sound signature.

Would appreciate thoughts or other amp recommendations.

Thanks! Lincoln