The other variable here is how loud you typically listen to music and the size of your room.
I also agree, pick the speakers that you like best and build around them because there are so many variables in speakers that picking the amp first leaves too many choices.
You also mentioned the possibility of high efficiency speakers. They go best with very low powered tube amps, IMHO, mostly SETs. Personally, I think that is the best sounding combination of all, and will completely blow you away (hence my username). You would be extremely surprised at how loud 2-3 wpc can be with the right speakers. If it were me, I'd go for a 45 or 2A3 amp, some high efficiency speakers and separate DAC.
I also agree, pick the speakers that you like best and build around them because there are so many variables in speakers that picking the amp first leaves too many choices.
You also mentioned the possibility of high efficiency speakers. They go best with very low powered tube amps, IMHO, mostly SETs. Personally, I think that is the best sounding combination of all, and will completely blow you away (hence my username). You would be extremely surprised at how loud 2-3 wpc can be with the right speakers. If it were me, I'd go for a 45 or 2A3 amp, some high efficiency speakers and separate DAC.