So I couldn't finish this campaign because I was incredibly annoyed by a particular enemy, that being the speedy crab things introduced inside the facility where you find the AI.
I don't mind that they're really fast, or that they swarm, or that they do quite a bit of damage. I don't even mind that they have knock-back. Frankly, I like the idea of a swarming threat that needs to be eliminated quickly!
The issue I have is that on top of the ludicrous speed, they are also near invincible bullet sponges! I could never kill a single one using my weapons, even after one or two full magazines!
The only way I could kill them is via melee, and even that only worked about 35% of the time. This is especially a problem when you have between four and six attacking you at simultaneously!
Keep in mind, I was playing on Easy and they consistently rocked me! I only got to the second part (Crows Nest) by avoiding them!
By the time I saw them again, I just gave up.
Overall, the campaign itself IS fun! A little lack-luster in parts, a tad clunky, but overall enjoyable up to the point mentioned.
I think greatly reducing their tankiness and reducing the knock-back slightly would significantly improve this enemy in the future.