For a combination of attractive and functional: good Osage Orange, antique Micarta, Desert Ironwood, the old African Blackwood that was really dark not the new brown stuff (which is also nice, but not quite the same to me).
My personal knives tend to be natural micarta or Osage orange. Durable, grippy and light.
The knives I produce tend to be micarta because it has the best combination of performance and value, which is how I make design decisions, but it's hard to compete with the beauty of natural wood. I've been smitten by this antique micarta because it combines the grip and durability of micarta with some of the beauty of wood. I got all of it I could find. I'll be sad when it's gone.