Puffy ack needs a full remodeling.
Instead of the explosion box always appearing with the selected target centered in it, balistics should be included. This means that the shells take time to fly up to 20k, 4 miles away and would have to extrapulate target position - same as the acks do. If the target turns, they will miss. This means that puffy ack is less effective vs. manuvering fighters and more effective vs. stright and level buffs on a bomb run.
Improving the AI to prioritize targets is a good idea. puffy ack is made to target high alt bombers. having it locked on some fighter in a dogfight at 4k is not what's it was made for.