I kinda already answerd what you asked. You can make a game from it, assuming you interject some game elements. Im not going to go into what we are doing with our project specifcally ( just yet ) but I think there is potential. What makes minecraft so enjoyable? Mining for blocks? NO!!!

What does make it enjoyable is the concept of being able to create whatever you like with a very basic process to do so. Look at the thousands of mods that have been created for the game, expanding its purpose and its enjoyable factor. Without these mods ( much like many games today ) people would have lost interest several weeks after they first started the game. So, you want an expansive list of what has yet to be touched?

- Questing
- Expanded Combat
- Skills and character+character interaction
- Story ( there really is none... )
- Expanding tools for creation

Those are just to name a few. As previously stated, Minecraft was more or less a guy mucking around with code until he made something unique. When released the people saw this and ate it up like crazy. From there the people made the game and that is the real reason for its success today. Are there better ways to code a game? Sure, but that doesnt mean that you should discount the concept of voxel based games because they are easier to code. I am remined of an episode from "The COmmunity" s3e20. The characters in the show play a 16 bit retro game that has so many rich features it would put many of the games today to shame. The game looked fun as hell too but it was only 16 bit and a platformer. ( i realize it was all dun of for show, but in reality, with enough time you could do alot of what they had )

TL:DR? You can make a quality game out of anything, so long as you put forth the effort and add something of value to the playerbase.

Listing the potential of voxels is almost like listing the potential for games which use 8-bit indexed color graphics, tilesets, and extremely small display resolutions. From the aspect of game mechanics, this field of possibilities is nearly identical to voxels' -- even more congruent than to traditional 3D graphics ('polygons') -- yet bounded by 2-dimensional space (and crappy colors). I certainly do have the imagination necessary to understand the potential of voxels when applied to games! Personally, I think the way we've figured to utilize voxels is somewhat idiotic, so far. They still have their place in computer graphics, although I don't think anyone currently understands, comprehensively, where they belong. Neither do I have the interest now to correctly elaborate how voxels might appropriately become useful in the future.