My default is stealth in this game, and I’ve been in this situation quite a few times. Having started the game with others, this first suggestion might not have been possible, but what I like to do is get the main objective out of the way, call extraction in, throw a turret right next to the terminal, drop all of my samples there too, and get right on the edge of “abandoning” extraction, prone. Enemies come, the sentry takes aggro, and I can usually extract with no shots fired. Doing this first, however, has an added benefit: as soon as the pelican is on the way (the timer reads 0), I leave extraction. The pelican hovers above extraction, and fires on anything in range. Instant everything obliterator. Then I’m free to do everything else I want to do without the stress of extraction hovering over, because extraction is hovering over (hey-o).

Outside of that last bit, the TL;DR is, in a word, stealth, and, to expound a bit, lose aggro, call extraction, drop samples at extraction, do not gain aggro, and best practice is to stay off of extraction as long as you can, so if you get swarmed, you’re not swarmed on extract, but somewhere else, and extraction is kept relatively un-rowdy.

Thank you for coming to my TED talk. Edit: spelling