If you kill the two Deckers that spawn after the alarm gets triggered, they don't respawn. Secondly, getting killed there just jacks you out with a lot of meat damage, which can all be reversed by a heal spell in the real world if you survive, so as long as you have a healer out there (not the jacked-in heal), you have as many tries as you want. All your ESPs come back when you jack back in, so it's easy to gank the enemy deckers - then you have all the time in the world to do the jacked-in part.
It's slightly more difficult to handle the huge ambush that comes after you at that point, but I was playing on a mage and there was a leyline in the room, so I just mezzed the big guards and destroyed the rest with an oppressive flood of fireballs.
Also - overwatch isn't a big deal if you pump dodge and body. High armour values also help - the problem is that most NPCs have pretty poor stat assignment (around 6 would be considered high for them, so they almost always get hit) - if you have 8 dodge or so, you can scout out rooms for your team, or use a shaman pet/drone as a sacrificial scout if really necessary. For resource management, some Nephilim Network guys are randomly cheaper than the normal hirees, so don't forget to check those out too. A lot of earlier missions can be run with only 2 or 3 people, so you can end up wasting a lot of cash on those.
shoutout bot guy
