I disagree regarding the "tablet" point - while the major DEs take some UI inspiration from tablets, in general they're still very much desktop-oriented. People

I disagree regarding the "tablet" point - while the major DEs take some UI inspiration from tablets, in general they're still very much desktop-oriented. People often complain about Unity for being "too much like a tablet", but actually try using it on a tablet and it's not well-suited at all in its current form. You might want to look at KDE and XFCE though - both are sticking more to traditional Linux desktop ideas than Gnome and Unity.