The one thing I would question is your need to go the separates route. With a $4000 budget, you're in a difficult range where a combo of separates may not be better than a really good integrated.
In fact, for $4000, I can't think of too many separate combos that would clearly trump an LFD Mistral or Plinius integrated. Both of those you could get brand new and still save at least $1,000, plus you would need one less set of interconnects ($100-500) and not have to worry about preamp/amp synergy.
I'm sure you'll get a recommendation about using a combo with good passive preamp, since they are much less expensive. In theory, you can get more performance for the dollar going this route, but it's unconventional and tricky.
In fact, for $4000, I can't think of too many separate combos that would clearly trump an LFD Mistral or Plinius integrated. Both of those you could get brand new and still save at least $1,000, plus you would need one less set of interconnects ($100-500) and not have to worry about preamp/amp synergy.
I'm sure you'll get a recommendation about using a combo with good passive preamp, since they are much less expensive. In theory, you can get more performance for the dollar going this route, but it's unconventional and tricky.