The texts we currently use in the "add block" light dialog are very technical and should be improved still, as this element currently looks unfinished.

I suggest to change the above dialog like this.

• Change the existing texts according to the wireframe above.
• Adjust the order to match the wireframe.
• Make "Image" the default selection.

Note that this is a worthwhile investment: although we eventually add a visual menu with icons for common blocks, we'll always still have to provide for a "more blocks" option where all additional blocks are mentioned. That menu will end up being in a light dialog as well.