>>717208854
It's been a while so my memory is a bit hazy, but..
>Ships
Any of them with a little luck on early shops for anti-crew weapons. They fall off as you get further, but they're all good early on. The Corbin is fantastic in Sectors 1 and 2.
Once you get into later Sectors, it's mostly Event Crew weapons, like the Zoltan Deleter.
As for more conventional killing via sending crew over, anyone works as long as you have a teleporter and a cloning bay. Medical bay is only useful for super defensive ships that have access to nano-machines and/or pheremones so you can sprint there as needed.
>Oxygen
Respirators Internal upgrade halves suffocation damage taken.