I dont think there is a wrong place to put structure, some might serve one purpose while others might serve a whole other scenario. my years Crappie fishing in different size BOW will tell me that in mid winter and hot summer times they move deep, up to 15' tho is pretty much max, seldom that deep, right now mine are close to 10' deep in my pond, but then during the spawn, and the rest of spring and fall they will be a lot shallower, around 5' for normal existence to real shallow for spawning.
Which to me indicates that you will need habitat in a variety of depths, and of course you also want to create habitat for their prey fish, which to me means a little shallower and more dense habitat.
I am fully convinced that you can influence the location of the fish, like lure them to your area by the placement, kind of, and depth of your habitat, of course also in relation to habitat that holds baitfish. to me, crappie don't require a real dense habitat.
And like Theo G said, put some in an area where the little kids and the old timers can fish it too,,, last thing you want is some big Crappie dragging an old man out of a boat!,, although that might make good habitat too.
