The cargo bay spawns cruisers, transport ships only fighters, same in Fronn.

hmm are you playing in hard difficulty? for myself on medium it only spawn butcher and fighter...

Yes at hard. at normal Butcher and some fighters, but you can go XT20 and back and the transport ships will be again there. Its better shot down them, instead attacking the cargo bay.

yep that's true while you are in hard, but in normal you've better shooting the cargo bay 'cause you earn a lot more; but again you're also true