upgrade suggestions from wilson sophias (original)?

Add sub/subs. Especially for EDM type stuff. No reason to sell the Sophias...

I’d add a pair of good subs or, even better, a Swarm from Audiokinesis and you’ll be set. 

oops. I forgot to respond to: 'what aspects of sound reproduction and system performance do you value most highly?' I have extremely eclectic taste so I've opted for a system that can do everything from folk music to orchestral to gothic-industrial. happily, it delivers - except for that very low (practically subsonic) bass.

thanks for the replies. I like everything about the sophias except the lack of very low frequencies (e.g. in electronic music). it also might be b/c I have tube amps, so SS might fix the issue. this might be as simple as getting a good-quality sub. system: CAT SL-1 MK III pre, Cary Slam-100 monoblocks (w/KT-120s).

This is a tall task.  Finding a "better" speaker than the Sabrina for under $10K will be no easy task.  In the end, the Sabrina is outstanding for the money and in its price range, is a strong value.  

You could get Magico A3s or S1 MKiis.  You could get Audiovector R3s.  But these are not obviously better, just different.  You need to clarify what you want to improve and maybe we can offer an opinion.  This is a tough one without that.  

What are you looking to improve upon, and what aspects of sound reproduction and system performance do you value most highly?  Also, what’s in the rest of your system?

Pretty sure someone here went from Sophia to Moab and was very pleased. If not I'm sure you can easily find a Tekton under $10k that will do nicely. Will have to be new however, as they rarely come up used. People like em too much to sell.