Most verbs are boring, in a good way. There are a couple of algorithms with their distinct sound and features, each one having a small amount of controls which allow one to fine-tune the sound for a purpose. Usually that's exactly what's needed to get the results one wants.
I feel the Nightsky is non-boring in an equally good way - it keeps the basic "algorithm" side simple, but in exchange, allows you to pop the hood open and tweak and modulate a lot of things that are usually unavailable or out of reach.
The base "algorithm" in this case is the "reverb core" - there are three of them, each with its unique sound and behaviour. Once you start piling modulation, pitch shifting, harmonic excitation, distortion and filtering on top, things get very, very interesting. Naturally, it's easy to go overboard: most of the demos online eventually show how someone really loves to make a reverb sound like a reverb run through an over-the-top wah or a distorted vibrato with pitch sequencing on top, and to me that sounds kind of gimmicky and cheap. But fear not: there's a huge palette of interesting and usable sounds one can get out of this one even if you're after "tasteful" results - from shimmery, crystaline, glittery sparse verbs to full-on bloomy ambience.
One thing it certainly doesn't really do is "real" or "classic" sounding reverbs, but you probably knew that already - and it's a pleasant surprise that aside the huge and weird stuff that you hear in the demos, you _can_ get nice, if proudly "artificial sounding", shorter and cleaner verbs out of it. There are much better and more versatile verb units for bread and butter reverb, this is just to say that it does sound good even without the shimmery modulated goodness and even with moderate size + decay settings.
Overall, I can't fault much - full marks from me for the purpose I bought it for.