To be fair this is basically just a texture pack, which is already something you can use. The real problem is the highly consistent UI design, differing in things as simple as if you have to use a keyboard or mouse to navigate a list.

Toady is understandably disinterested in putting time into that element of the game, and I think he had a bad experience the last time he 'outsourced' it.

It's not just a texture pack in any way - just read the dev blog. They are also overhauling all of the UIs, adding mouse support to everything and so on.