Is a Missile D-Bomb to big/beefy to use on a shakeyhead in your opinion? What about something like a Biffle Hardhead?

They'll work good on a hardhead, pretty bulky for a shakyhead though unless you have a wide gap hook. 

I really like the DBomb for a Hardhead as it seems most Biffle Bug/beaver baits tend to tear in the longwise groove in the body.  The DBomb is meaty enough to hold up to repeated fish catches and you can texpose the hook in the bait’s rings.  DBombs are just great all around fish catchers.

The scaled down baby d-bomb is pretty great on a shakey head, it's a bit smaller profile than the actual d-bomb though