If you like the "French" sound (sweet and detailed, but not hard or overly analytical) I might suggest that you pair your YBA amp with a pair of speakers that will mirror that sound quality.
JM Labs/Focal, Triangle and JM Reynaud all make excellent speakers. It would be had to beat any of the Focal Utopia series, but all of these sound great. If I could make a gross generalization and characterize the three manufacturers, to my ears Focal is the most detailed and JMR is the sweetest and provides the best soundstage. Traingle is somewhere in between.
I recently bought a used pair of JM Reynaud Offrande speakers specifically to use for vocal/classical/chamber/opera music in my new (small) listening room. They are large (well, deep) stand mounted speakers that present a very wide, deep rear image like no other speakers I have ever heard.