I'm a fan of capturing enemy ships intact if possible, due to the greater rewards involved. With a teleporter, a couple of Mantis "spare" crewmates and an S. Bomb, this is very effective.
However, I wonder if there are any remotely effective techniques for destroying the crew while leaving the ship intact, if you don't have a teleporter? (Or equivalently, if you have one but no feasible boarding party.)
I've managed to asphyxiate the crew once before, but in general I find this to be very difficult - it's hard to keep the O2 system down without causing extra damage to the ship's hull. And since it's a waiting game for the O2 levels to drop, it's likely necessary to disable the enemy weapons/drone systems too, causing further "collateral damage" to the hull.
Could ion weapons be a feasible way to do this, or would it take two or more (i.e. an unlikely number to find) to pull this off?
Are there any other approaches that would work - fire, for example? Has anyone had success with using fire bombs/beams to specifically target the crew? Did you have problems with rampant fire causing damage to systems and thus destroying the hull?
In any non-boarding case, I recognise that you almost certainly need to know where the enemy crew is, so I'm assuming that upgraded sensors, or a Slug crewmember, is a prerequisite.