~$15K floorstanders: opinions sought

It would help to know about other considerations, such as room placement (in the corner, out in the middle of the room?), room size, etc.  

For corner placement, I like the Audio Note line (the specific model will depend on room size).  I don't know what you would think about the looks of a plain box, but, they come with very nice wood veneers.  Again for corner placement, the Gradient Revolution is another great sounding speaker.

Out of the corners of the room, the best bargain in speakers in your price range come from Charney Audio.  The look is a bit funky, but, you might like them.  They are very efficient, so they might not be the best match for high-powered Krell amps, but, they are simply amazing.

Given your preference for the sound of Spatial speakers, I think you might also like the sound of something from SoundKaos.  I heard their Model 42 (narrow oval shape) and it was quite good, although it might be a little bit above your price range).

Of models mentioned above, I like the ProAc D48R and Vandersteen Quattro.  

Larryi, thanks for those, very interesting! The Charney look a bit like Rethm and Vivid. I always love learning new stuff. 

Some really rave about the NSMT Model 100's too 
 
https://www.nsmt-loudspeakers.com/

The Legacy speakers look great in person, not so much in photos. So I do suggest checking them out in person. I own the Signature SE. The Endeavor MK2 was my second choice when I was speaker shopping, I'm sure the Endeavor SE is very good.

Other aesthetically pleasing speakers in that range:
Proac D48R
Monitor Audio Platinum PL300 MK2
Dali Epicon 8
Audio Physic Codex

However, if aesthetics is the main thing, whatever Sonus Fabre fits the budget. They just look beautiful IMO. And they sound good enough.

Thanks nitewulf, I have a huge crush on the SF Olympica Nova series, which--weird grill aside - - are stupendously beautiful imo. Thanks for the ideas!