Depending on the size of the dock .... I'd have at least one "brushpile" UNDER the dock and/or one tree hanging off the side of it. You could also consider placing a couple of brushpiles out in front of the dock (if deeper water is present there) and within a short cast's distance from the front or front corners of the dock.

Where you place these "attractors" would depend on depth of water, and whether or not water level changes (if applicable) would put those attractors in the way of your boat (or possible swimming area). Another factor could also be whether your dock is on poles (stationary) or floating.

Clear water and those depths are not real conducive to Crappie hanging around "often" ... but, the additional "cover" you intend to place may help draw them in. They'd certainly take notice during the spawning period !!