+1! It's useful for more than just getting the LVTs feet dry. A surface action tactic for disengagement was for the tin-cans to lay down a smoke screen behind a fleet as it retires, or between opposing fleets, to allow ships with smaller guns (and thus, reach) to get within gun or torpedo range of a heavier opponent. I'm not sure what the frame-rate hit might be, but we already have smoke for GVs; I'm not sure it would be any worse if a ship was throwing them instead of a GV. Of course, there's all kinds of mischief you could cause. You could lay down smoke over an entire airfield, disrupting flight and ground gun ops.
Part of the problem with fleets in AH is they all are created equal. Same speed, same main/secondary guns, same armoring (or rather, no armoring to speak of; just a damage rating). Makes sense for the MA, but lacks the nuances of real naval combat.