You don't need to bang a crank into cover, or along the bottom. What triggers a strike on a crank is most often from a quick change in direction, or speed. I use them as search baits throughout the water column and a stop and go retrieve produces in that open water.
One suggestion; If you'll be bouncing it off rocks, bottom, wood, or whatever, you may want to up that leader to 10lb. It will hold up better. Either way you go, check your line above the bait and retie frequently.