Personally, I never really thought that there would be audible benefits to active. To me, the benefits, like you said, are in being able to tailor the response to taste and to even customize the slopes, points, and other filters to maintain the desired "sound" in a much wider range of rooms and placements.
I would think a unit like a DEQX or a miniDSP 4X10HD would be invaluable to a designer and builder for experimentation with different drivers and crossover points without having to build or tinker with the passive crossover until you'd settled on a final design. That is, unless you've got some pretty good computer software and a ton of experience.........so maybe you don't need anything like that after all