threejs.org is very easy to work with. It is a lot less complex than Unity. It is based on Javascript. I like the feel of it and the community that is built around it. Ethan Mollick used it to create his Library of Babel application and his Umberto Eco's library application. It has been used to create some very interesting book applications.
I also think threejs is great. It's the only dependency in this game. The game engine itself is completely custom.
Wich I had your level in 3D :'). That's incredible !
That was fun! Good Job!
Thank you! How far did you get? How many game modes?