I had an idea a while back to convert the plasma pistol into a shield while retaining its regular functions.
Ok here goes.
When you start up a charge shot you can release and shoot as usual. However when using a charge shot and taking incoming fire (except explosives) they will all be absorbed into the charge making it bigger and also acting as a shield. The more ammo the ball takes in, the more powerful it becomes when released however to add strategy to the mix, if you overload the charge shot with bullets and plasma it will explode so you cant give keep increasing the size, you must be careful. Also, it prevents you from overusing it as a shield. Also this is good as you get a shield and at the same time its also an output weapon too.
It also adds strategy to the attacker. You see your foe charging up a ball of plasma, do you:
A) Unleash round after round of round of ammo onto the ball trying to overload it thus exploding your opponant while risking the fact that if they manage to hit you when released it will cause you more damage.
B) Cease fire thus not risking extra damage however, you cant get up close and must arrange for a snipe on the overcharger.