While most woods will sell, ornamental grain has an edge. Outdoor surfaces need a rot resistant quality, but that's the customer's worry.
You need to define a sawing direction that will minimize cracking as well as show off figure.
The hardest part is assigning a "value" to the slab and sticking with it. It is you, the seller/marketeer who creates the market. Just as in many other endeavors where a natural product is being sold, it is as much your job to plant the seed for the use as it is the customer's looking for a solution to a problem. A lot of figured woods are sold because the seller planted the "seed" .

This is why it behooves a sawyer to study the woods in his area and become an expert. The customer must believe you. Pass the customer a bunch of bull and you will be found out in a very short while and lose all of your credibility.