Coolhandluke, I’m a fan of separates, but with your budget it would be tough to get a decent preamp with those outlaw monoblocks. BTW, I think their price is back up to $399 each, which leaves bery little $ for a used pre.
With all of the features you are looking for, an all in one component makes more sense, because of your budget and desired feature set. But if you are getting more interested in separates, the Schiit Audio Vidar amp would be an option. I wouldn’t recommend their preamp Saga because as a passive pre, it lacks the dynamic sound of an active pre( I had 2 Sagas before I bought the Freya +).