Need advice/opinion in choosing Vandy 2ci or Thiel 1.5

2jjss49, I’ve heard this criticism across various Thiels including larger models from time to time. My experience suggests that this might be more to do with the sloping baffle and ceiling reflections. When I moved from an 8’ ceiling to one with a 15’ peak the soundstage with the very same system including Thiel CS 2 speakers (soon after changed) expanded quite a bit vertically. A bit of room treatment could go a long was to mitigating what you’ve described. FYI, Most Thiel's and Vanderseens are designed to be listened to at standard seating positions, (which interestingly varies by only a few inches for almost everyone) at a minimum distance of 8' for time alignment driver integration. 

Double confirmation as I have two pair of Vandy and recently parted ways w T 2.3… w 7 pairs of speakers, something had to give…
OP that room that amp better served w new pair of 1ci, I think TMR has a slightly used pair for under $900.
have fun, enjoy the music !
so cool you are helping !!!!

it was some 20 years ago, but my one very notable point of recall on the thiel 1.5’s was their lack of height… seemed to have the soundstage rather low (waist height)

I think that those speakers were noted to be romantic. ;)

(I would have been spinning the Barry White discs.)

I've never heard either one, but I'd think with both of these, their Vifa drivers must be pretty darned old by now so you might want to just check condition of the surrounds and cones.

I have to agree with @Holmz re: the Vandersteens 2’s unfussy compatibility with various amps. One of the most accommodating speakers I know of in that regard. Though I do have a particular fondness for PSE, McCormack and Audio Research with them.