Oh and I am not even the artist on my team... but, I made all of those textures too. :)

Nope, I haven't seen that. Though looking at that, we already have support for most of that. Stonehearth is using the one from www.minidesk.com . Right now other than Unity3D we are doing it all ourselves and have 100% source code, and 100% control. This means we have 100% flexibility, but also puts a lot on us. They above screenshot was done after only a month of development, so I do not really see the need for a new engine. Also, Unity does stuff that voxelfarm does not. I actually would not be surprised if Stonehearth is being done in Unity with the Qubicle Constructor Unite plugin. Since, I have plans in the works for how to construct all kinds of voxel objects using many voxel styles besides just cubes... I think we're coming along rapidly... and I am pretty happy. I am working on changes to the above system now to add some flexibility, and to add in fluid dynamics and such. Right now with plans for fresh water, salt water, and lava.

Have you seen http://voxelfarm.com/vfweb/engine.html voxelfarm engine? I have no idea how much they charge for it but I see there are at least 3 games in development using it.

I wouldn't call it a prototype of any game yet, since it is me building the tools for the game. Though it is a glimpse of what will likely be in my game... or several of them.

Run Me is a prototype of me playing around with my Terrain system... :)

Is Run Me a prototype of your game?