change trade missions for combat missions

How can I change the trade missions that we get in some trade stations or orbital bars with combat missions?

For Example: If you are a puddle jumper:
Go to lucian alliance territory and destroy 5 (or other number) death gliders (or one al'kesh).

It would be usefull not to destroy the trade missions on the planet hail menu.

right, this is an interesting one, as the trade missions are based upon the cargo that is transported. Something I'm experimenting with in BM3 is adding the missions into the actual code in the game. For something as specific as you want, I'll have to do a little research and experimentation.

Perhaps if it would be easier, instead of cargo, you could beam down a bomb onto specific stations.

it's set up so that you can only transport things to planets

Well you can always deliver bombs, assasins and other things to planets to help deliver a coup.

or you could do escort missoins