I wondering if it might be worth the author editing the mission slightly, as there was one play through that I had where...
I almost saved the Rhebis as it had not collided with the Riga debris and I had been able to perform surgical strikes on the super destroyer to stop it causing catastrophic damage. The only reason I had not saved it was because I had got lazy and stopped destroying the anti fighter beams which were enough to give it a killing blow. The edit I would suggest is maybe to have the Rhebis enter the mission on lower HP and maybe adding a note in the briefing that it is having problems with the reactor.
Please note that the above is just a suggestion and I think it would help iron out any confusion that others might have when they play the campaign... call it a little... polish... maybe!
Overall though, I have been enjoying the campaign and it has been good fun. Just need voices next hehe