It would be a great idea to add in 3D game structure so that libraries for it aren't necessary... For example, to make a wall, you must specify a texture for each side of it to appear as, then specify its width and height. For the Camera, make a first person and behind shoulder view.
Make it flexible, an example of what BYOND could become is Roblox. Although instead of only containing 3D games it will contain 3D, 2D, ISO and Tile-Down. I know that this idea WILL definately take a long time to make, but it will bring loads more players to BYOND and will bring BYOND to its 3D stage.
Being a developer myself, I get kind of bored of Overhead and Isometric viewing, I do hope that my idea is implemented.
Thanks for listening,