In this context "raking view" means you have a wide view of the marketplace. A "narrow view" means you can only see a small part of something, but when you have a "raking view" it means you can start by looking at the left side of the market and then turn your head all the way to the right to see the right side of the market. You can't get much better than that, so it's a very good view!
By the way, "raking gunfire" is when the person quickly moves the gun from left to right while firing bullets, and a "raking searchlight" is a light that moving left and right in the same way. So you can use it in all kinds of situations. But the thing to remember is that "raking" has this feeling of moving left to right and then right to left, back and forth, again and again.