Most of my last six hours has been spent exploring caves and gathering rare materials. I haven't actually had time to build anything out of those materials, but assuming I still wanted to continue playing the game, I'd at least have enough bricks to build something tall and imposing out of onyx.
The other thing I've been doing is visiting the community islands that people have put online. The advantage of doing so, aside from voyeuristically peeking at other people's creations, is that there is a certain character called Malik the Cursed. He's like an adorable goth version of the Jin creatures you trade scrolls from. If you give him a gold ingot, he'll give you an item from the special nightshade set. Malik emerges from a special item you have to build, but each character has only one member of the set. So you have to visit other players' worlds and feed gold ingots to their versions of Malik to collect the whole set.
Thus the necessity for the rare materials. Unfortunately, the Windborne online community is pretty dead, so I was only able to get about a half-dozen of the Nightshade items. Looking at the other players' constructions was cool though. I really admire the creativity and industry that went into building those islands.
In theory, I could attempt to match those creations (though, admittedly, my base level of architectural and interior design skill is clearly less) and it would be an amusing use of my time. Even in its incomplete state, Windborne is not that bad, and it's undeniable that the sorts of things you can create with a full palette of tools are breathtaking. It's got a unique and appealing visual style that helps it stand out from all the other voxel crafting games.
However the problem is that it does feel truncated. Even with the wide variety of cosmetic options (wider, in fact, than any game I've ever played), you can still see the seams where new features were going to be added. I really want to do more with the Jin, and collect a whole menagerie of cute little pets, and find equipment and artifacts that improve my character's abilities. There are places in the user interface that hint at these systems, but they just dangle there uselessly, never to be finished.
Ironically, I think Windborne would feel more complete if these vestigial features were removed. Then it would just be a slight little block-stacking game whose main draw is that you can build substantially more attractive buildings than in more sim- and survival-focused crafting games. As it is, you can see how it was chopped in half, and thus you can never quite forget about what it might have been.
My final assessment is that playing Windborne was . . . nice. It didn't hook me like Starmade and it didn't challenge me like Minecraft, but it was pretty and there was plenty to do, and I'd like to go back and one day build something really incredible, but honestly the basic gameplay lacked a certain . . . "fire." In the end, it was merely pleasant. And while pleasant isn't a bad thing to be, Windborne simply has too much competition for that to be enough.