I don't hate the UI choice made in Dune 3D. But I still think the menu bar approach is the best for complex applications.

I don't like the GTK crowd's approach in regards trying to make everything work within the GNOME design paradigm. It doesn't look good on all platforms, and feels more hamfisted then anything else.

Sad to see some in the comments criticise GIMP so hard, I get it doesn't compete with professional proprietary software. But it's still a very useful image editing tool, that I use a lot.