Currently every plane can drop any type of bomb, even the smallest fighter can carry a nuke designed for a large bomber.
same problem at tanks. every tank can fire any type of shells. So a AA Tank can fire Artillery Shells at the same speed as AA Shells.
A Ammo Variable like for the AA Guns would be nice, so the content pack builder could limit the bombs and shells to some specific types.

I believe this was added for the next version.