The editor should have an automated tutorial mode :)

I find it difficult to create simple things, like variously colored blocks. The prefabs that come with the editor are a little lacking, and I have to create new prefab types to add stuff to the level.

It would feel more intuitive to me to work as if in ms-paint, as opposed to a modeler, or have such an editing mode (probably as default). I hate modelers, which is part of why I was looking foward to this editor.

Supporting the keyboard would also be less fiddley than the mouse, or having some sort of sizable grid system.

Then again I only messed around with it for 10 minutes.