If female vocals are your thing then I would go with either a tube pre-amp and good SS amp (fair amount of Class "A" bias), or go tubes the whole way in a pre and amp. the Mac 275 is a classic for sure, there are good used options in ARC, CJ as well.
FWIW, I'm presently using a pair of Rogue M-150 MonoBlocks and am more than happy with their performance.
With respect to SS amplification, I'm a big Plinius fan, owning a SA-102, it is a superb Class "A" amp that you will be hard pressed to better, when they come up for sale on the "Gon" ($2800-3000) they don't last long.
So, given your 4k budget, I say be patient, go seperate, that way your next upgrade will be incremental !!