Ok well here we get into a fundamental question of whether one is looking to buy a DAC or a more central component of a system, and also if the end user just wants to save money by not buying a preamp at all. I think a DAC should be a DAC mainly, and do that as best as it can. In many cases a good or matching preamp will sound better than what most DACs can offer, but at a much higher cost.
If a preamp/volume control is added, ok. If it's digital it can be low cost to manufacture and can by bypassed easily. If analog it's likely better if done well, but then adds more cost. Then you add preamp functions (how many inputs, phono too?) and you want this at high quality, then cost goes up and up and people with expensive preamps or integrated amps have no benefit at all. Good connectors alone can be very pricey.
I think many people will carefully match amp/preamp preferably from the same brand for synergy reasons. At least I do in my more expensive systems.
To return somewhat to the topic of this thread, ATC makes preamps and that's what I would get plus a DAC of whatever flavor suits the listener. At the cost of these ATC's and if you like their amps (which the OP obviously did by choosing actives over passives) I'd just go with an ATC preamp and not try save money going with a combo dac/pre. What if you want to change the DAC one day? You are limited to DAC/Pre combos, and the preamp part might gel with the ATC or not...