Storyline: 3
There is a palpable feeling throughout the command briefing and the mission that much is happening behind the scenes. Unfortunately, the player is never really told what that is. The readme says that the background is intentionally vague to avoid spoiling the associated campaign, but the standalone mission suffers from it. We don't know who the Syndicate is or what rumors were sparked by the "incident" of three days ago. (I have a hunch that the Syndicate is a reinvigorated Regulus Syndicate, but that isn't very clear.)
Fortunately, these problems don't detract from the immediate mission-specific storyline, which works decently on its own terms. The atmosphere encourages a personal investment in the outcome of the mission; and there is a large amount of very well written dialogue. I just wish I didn't feel like I was playing with amnesia.
Balance: 2
I'm going to have to dock some points here; the balance is too skewed for what the mission is billed as. With the swarms of Shivan fighters and capships, this felt like one of the 70th Blue Lions missions in the main FS2 campaign, except without the appropriate hardware. I was satisfied to be able to outfit my wing with Myrmidons sporting Prometheus S's in the four-gun bank; but everything else was underwhelming. Ulysseses, Lokis, and Perseuses aren't suited for extended firefights; and the Prometheus R is crap. At least there were enough Subachs to go around.
Considering the difficulty, I felt the briefing was rather unfair to the player. Given that I was battling wave after wave of fighters and bombers with hardly a break in the action, I had barely any opportunity to give the Narvik particular attention. Also, considering that the entire blockade force was flattened in a matter of minutes, the mission's outcome should not have depended on the protection of a single unremarkable ship.
Design: 5
I was extremely impressed with the mission's design. The mission designer really showed his proficiency with FRED here, as the mission is chock full of well-coordinated events. Not only are all the standard requirements of good mission design satisfied, but the author spent extra effort to give the mission a generous helping of polish. The messages are displayed for exactly the right amount of time; alt-names are used on many ships in appropriate ways; there's a clever use of a freighter to deploy sentry guns around the node. There is even an event which checks to see if the Orien has been disabled and sends an appropriate message -- an indicator of scrupulous attention to detail.
There are a few things that could be fixed here -- for instance, since Beta has already been patrolling, they shouldn't be in the starting loadout. The messages and debriefing claim that Nahemas are threatening the Narvik, but they're actually Nephilims. There are also a few spelling and grammar errors. However, the mission has so many things going right with it that I can't help but overlook these minor flaws and awarding this category a solid 5.
Gameplay: 4
This mission was quite a lot of fun to play. The dialogue was interesting to read; the events and ship movements were fun to watch; and, as said before, the atmosphere encouraged me to feel personally invested in the mission. That can make or break the gameplay experience, since whether the player quits in disgust or perseveres despite the difficulty can hinge in a large degree on his personal investment in the mission and its story.
I only have a few complaints in this category. First, the long gap at the beginning of the mission before any action happened. It was interesting and far from boring, which was a good thing; but it was a little tedious to wait through on the second try. Second, the endless waves of fighters and bombers once the action started allowed little time to stop, breathe, and assess the situation. Finally, on the second playthrough when I had finally protected the Narvik long enough for it to escape and initiated the jump sequence, a swarm of Maras jumped in and pulverized my fighter just before I could jump out. That's infuriating, especially after a sixteen minute long mission. The mission designer ought to have ship-protected my fighter once the Return to Base order was given, or taken other steps to allow the player time enough to jump out.
Overall: 4
The average of all the categories is a 3.5, but I'm bumping that up to 4 because of the fun factor and the extremely polished design. With some attention to the storyline and balance, this mission could easily earn a 5, in my estimation.