The "redmond classic" style would look a bit unnatural today given how common high-DPI displays have become; you'd have to thicken the pixel-perfect visual elements quite a bit to even make it look acceptable in such conditions.

In general, I find that any simple theme with clearly-visible 3D styling is good enough, and Adwaita (though maybe a bit too flashy for my preference) gives us that - with the extra bonus of being touchscreen-ready by default, which is also quite a big deal these days.