I am just playing around here. This is just a speculation, but I think this would be cool.
Actions: Barrel Roll, Evade, Target Lock, Focus
Upgrades: 2 Missiles
They basically fill the role for people who want to field TIE Advanced just so they can shoot missiles, but they don't want to pay the expensive point cost.
Possible Changes: no evade, and proton torpedo instead of one of the missile slots.
I think this load out for a TIE Bomber would be far from overpowering, fullfill a useful nich in the Imperial force and add to the game.
I don't have an equally good ideas for the B-Wing