The decision to pre-emptively evacuate Capella, and to continue evacuations even when it seemed that the Shivans had been beaten back, might have been one of Command's brightest moments. They managed to save a lot of lives that way; from reading the mission briefings, it seems as though few people died outside of those in the last few transports who couldn't escape the supernova. It's a little reassuring to know that even Command can get something right.
Regarding the Sathanes, I really wasn't considering their fighter complements, which is kind of a big oversight.
You would need either a large amount of cruisers, a lot of pilots with skill levels similar to your own, or some sort of other anti-fighter defense to deal with them, presuming that the Sathanes dispatched their full complements. (Just out of curiosity, I know the Sathanes could theoretically carry a massive amount of fighters/bombers, but did the game ever give an actual value?) Regarding backup for the Sathanes, we don't really seem to know how many other ships the Shivans had. Even if it was a moderate amount, the setup I mentioned above could take care of anything cruiser-sized or below relatively easily. The real problem I could see would be with Ravanas, due to those forward-facing turrets, but they would be easily stopped with the Bearbaiting treatment. I could see how multiple capital ships coming through at once could be a problem, but as far as we know, there really isn't enough room in a subspace node for that to happen. It might be an interesting exercise to set up a test mission to try this out on a smaller scale.