Don't know offhand if it doubles into 4 ohms or not, but I found the Marsh A400s to have a very refined presentation with lots of tonality and natural detail. It's very good looking in an understated and tasteful kind of way, and it comes in very close to your price range. From what you described you're looking for this amp's character should fit almost perfectly. I would not think either the Bryston or the Aragon would give you what you're looking for, and the Specton being a digital amp would seem unlikely to add a little warmth, although I've only heard it at shows so I don't really know.
Don't know if the power characteristics are there, but you might also consider a Conrad Johnson solid state amp, and I'd also echo the Classe recommendation. Best of luck.
Don't know if the power characteristics are there, but you might also consider a Conrad Johnson solid state amp, and I'd also echo the Classe recommendation. Best of luck.