How about a 2-3 point Modification (so all factions can use) that allows the Bomb to be deployed in front of the ship instead of behind? You run the risk of hitting your own Bomb, especially in close-quarter combat, but you'd be able to turn to adjust for that. Something to think about at least.

So make it more expensive?

How bout a modification that increases your bomb load for only 1 point extra? So in theory you can carry 2 Proton Bombs for 6 points. 2 Seismics for 3 points, etc. Maybe have it only work with Bombs and not the mine so you can't spam mines everywhere.

How about this for a slightly whacky fun list / strategy for bomb style ordinance:

Load up 3 GSPs with ICT and proximity mines

For your first move, immediately k-turn and at the start of your next turn lay the mines.

They just slowly 'orbit' the mines doing your best to keep them between you and the enemy.

As long as you aren't up against anything with a turret, your opponent is going to have to be more or less in line with the mine in order to get a shot - handing you the opportunity to ion them straight into the mine.

Probably not as easy as it sounds and the damage potential isn't particularly high - but in terms of sheer oddball goofiness it's a surefire winner in my book