Check out the Alon Acarian IV's ($ 1875 used) for a full range speaker that should like your BAT's. Also
there are two NHT 3.3's for $ 2K and under used which I still prefer(slightly) to the 2.9's even if they do not open up as readily at low volumes. As a Vandersteen owner, I certainly second the 3A recommendation! If you are feeling electrostatic, you can look at the used Quads(midrange legends, so-so bass) or used Soundlabs(good full range stats- not quite as subtle as some) well in your price range, if SAF is not an issue. What a fun problem! Lots of great stuff, especially used. If you had four power amps and some patience, I would even look at the Infinity IRS Gamma for sale for $ 1,500. Not pushing this last idea, mind you, just a thought. If you spot some Hales(Revelation 3) they are an overall strong performer, but are hard to get used,(they go fast) and too much money new.
For new speakers in your range, try the Newform Acoustics
ribbons- easy loads and truly magical. Forget finding them used( I have been looking.) Good luck!