Why not give each character a Generic Ball along with the Generic Beam? I've seen people asking for balls such as that used by Buu in the Babidi Saga against Gohan. The other Z Fighters used balls every now and then - Piccolo had a large ball attack (that is actually one of his named, but didn't make it into ESF) and Gohan threw a giant one at Frieza when he lost his temper. A Generic Ball would handle them all nicely.
It could simply be a right click for the Generic Beam attack, like the Earth Spirit Bomb is a right click on the regular Spirit Bomb attack. Weak and flimsy, like the generic, but powerful enough if your PL is high. It should probably be instantly destroyed by most beams as well, to prevent it being used to avoid power struggles.
I do have another suggestion, but it's kind of complicated and some would say unnecessary. Cell right now uses three voices. Semi-Perfect Cell for the Gallit Cannon, regular Cell for the Kamehameha and Perfect Cell for the Special Beam Cannon.
This seems a little wrong, and a possible solution when Perfect Cell is added would be to separate the attacks amongst transformations. Regular Cell is only able to use Kamehameha. When Cell transforms to Semi-Perfect Cell, he loses the Kamehameha and gains the Gallit Cannon. Then, when he reaches Perfect Form, he gains Special Beam Cannon and also gets Kamehameha again (he used it enough times as Perfect to get a decent sound clip.)
The problem is that I doubt people would like to transform and lose Kamehameha for the less-powerful Gallit Cannon. Still, it could be seen as 'compensation' for the increased power/speed the transformation provides, and it pays off when you finally become Perfect.
It could simply be a right click for the Generic Beam attack, like the Earth Spirit Bomb is a right click on the regular Spirit Bomb attack. Weak and flimsy, like the generic, but powerful enough if your PL is high. It should probably be instantly destroyed by most beams as well, to prevent it being used to avoid power struggles.
I do have another suggestion, but it's kind of complicated and some would say unnecessary. Cell right now uses three voices. Semi-Perfect Cell for the Gallit Cannon, regular Cell for the Kamehameha and Perfect Cell for the Special Beam Cannon.
This seems a little wrong, and a possible solution when Perfect Cell is added would be to separate the attacks amongst transformations. Regular Cell is only able to use Kamehameha. When Cell transforms to Semi-Perfect Cell, he loses the Kamehameha and gains the Gallit Cannon. Then, when he reaches Perfect Form, he gains Special Beam Cannon and also gets Kamehameha again (he used it enough times as Perfect to get a decent sound clip.)
The problem is that I doubt people would like to transform and lose Kamehameha for the less-powerful Gallit Cannon. Still, it could be seen as 'compensation' for the increased power/speed the transformation provides, and it pays off when you finally become Perfect.