Starkman1 asked about how figured woods are graded. The grading system varies with the different industries. Furniture and guitar building will usually grade figured wood by a system of 1A to 5A figured woods. 5A means the piece has highly visible figure over 100% of the surface. 1A barely noticeable figure over a small area. Other grades such as Exhibition Grade, Specimen Grade and Museum Grade are used, not always accurately.
My grading system steers way away from the standards.
I go by; Pretty cool stuff, Way cool, Wacko, Bizarre and some other rather colorful terms. Tends to embarrass my boss sometimes when I am waiting on a customer. But I help them to find some of the most dramatic and unusual wood they have ever seen. They all leave happy.
All joking aside. Every type of wood will have countless variations that can be multiplied further by how it is cut. Quartersawn, Flat sawn, Rift Sawn or wven crosscut for end grain. In my opinion, the best wood is what you like best. I really like all the variations of redwood. But then I am in the midst of the redwoods and see a lot of really cool stuff.
Enough of my rambling. Some of the other knifemakers thought I should ask what the knife collectors like to see. By posting photos of knives you like, it gives them a better idea what materials to use. A block of knife handle wood can sell for as low as $5 up to over $100. But when it is going on an expensive custom knife, I'd pick the expensive unusual wood every time.