Okay, I failed the mission the first time round. I found a few little grammatical errors in the briefing, I'll list them here.
Nitpick mode activated.
Stage one should have "after recharging its drives", not "after recharging the drives". Also, "supposed to jump near Epsilon Pegasi node" should have a "the" before Epsilon Pegasi.
"However, it didn't happened" should be replaced with "However, this didn't happen."
Stage two should have "convoy's escort" instead of "convoy escort", "heavy losses" instead of "heavy loses", and "carrying XM-53 container" is missing a "an" before XM-53.
Stage three should have "the contents of the XM-53 unit are highly classified" instead of "the content of the XM-53 unit is highly classified", "assembling the repair crew with required spare parts" should be "assembling a repair crew with the required spare parts". Stage 3 is also missing a period at the end of the last sentence.
Stage four: instead of "This cargo is critical for the GTVA, maybe even for the whole humanity", I recommend rephrasing it to something like "The survival of the cargo is critical to the war effort, and therefore critical to the survival of humanity". Also in that stage "protect it by any means necessary" should have "with" instead of "by", and "but in this whole Capella Evacuation mess" should have "with" instead of "in".
Regarding the scanning of the cargo, that sentence should have "will be considered a traitor".
The last part should have "get out there and do your job" instead of "go there and do your job".
That's all I could find there. The briefing set up a very nice atmosphere for the mission and I commend you for that.
Like I said I failed the mission the first time so I can't comment on that. I'll do a more determined playthrough later today.
Regarding the fail debriefing, I think that "time will show if we can recover from this lost" should have "loss" as the last word instead.
Also I noticed that the debriefing for failure has no recommendations. It's generally a good idea to include some possible solutions for what might have gone wrong, even if it's pretty general.
That's it for now. I will post more once I replay the mission.