Ok. So, there are some things you definitely need to fix. Mission eight is now fine, since you just corrected that. Mission 9 is not bad already, and it has potential to be even better.
Only, the aeolus cruisers are isolated when they jump in, so it's dangerous to tell them to jump in too early because they get destroyed by the fighters and bombers that are launching from the destroyers. If instead you have their arrival set as near one of the leviathan cruisers, then they can benefit from each other's anti-fighter beams, and it's not as difficult to cover everyone.
In mission 10,
You have Gamma 2 set to invulnerable instead of Gamma 1, and in the next mission he isn't invulnerable again.
Also in mission 10,
if you give orders to the cruisers to attack any of the capital ships in particular, it'll cause that ship to move off its path and then get in the way of the other cruisers when it returns to follow its waypoints. I suggest you turn orders off for them.
In Mission 11,
the mentu is going 35 m/s. The fenris is going 20. The leviathan is going 10. And they're going in a straight line. The first time I went through the mission, the leviathan attacked the mentu, but it didn't change course: all of the leviathan's attacks hit the fenris and it died. For some reason, the second time through, this didn't happen, otherwise I'd still be playing. What did happen, though, is that they were sandwiched together.
In Mission 12,
This is more of a immersion issue, but I had no idea there was an escape pod, because there was no message that said there was an escape pod, neither did it show up on the escort list, and neither did it appear in the directives. Adding some kind of message that there is an escape pod would really help.
In mission 13,
The entire mission is based on whether you can take down the beams. I failed the mission after I destroyed the Typhon because I had only taken out 1 beam, despite the station being safe. There is only one main beam per side of the ship, and it's pretty difficult to use them both because of this. Also, nothing else happened in the mission after the Typhon was destroyed. You should probably set the events so that they will react to either the beams being down OR the Typhon being destroyed.
Mission 13 was as far as I got. Good luck!
EDIT: Got through the rest. Missions 9, 14, 15, and 16 are probably my favorite of the campaign.
Mission 16 was a pretty well done large scale battle and I experienced no problems.
There doesn't seem to be anything further that I could point out, except for two things.
Missions 17 and 18 are too hard. There are too many fighters. In mission 17, your team has 12 fighters and 10 bombers (with 6 bombers in reserve). At least 15 fighters are constantly attacking your wingmates after the three cruisers are destroyed, and your only hope of finishing the mission is taking down the turrets as quickly as possible after the cruisers are down. If you wait for the bombers, then your entire squad is destroyed before the destroyer goes down, and there is only a low chance of you surviving against 15-odd fighters with only a few invulnerable wingmates and a few AAA beams on your side. Add some delay between the wing respawns, and this should help to make it marginally easier.
Mission 18 was pretty good except that it seems like you must take down the beams of either the Typhon or Hatshepsut. Maybe I didn't play the mission right, but it feels like trying to fend off the figheters and bombers is a little bit unimportant in the face of 4 enemy beam cannons.