Some things I've learned about boarding
Good shields and possibly 1-2 defense drones against missiles will allow you to easily take any non-AI ship without a med bay.
To handle ships with a med bay, first teleport your guys into a 2 square room close to the med bay. When the defenders start retreating into the medbay, hit it with a bomb and immediately rush in with your guys.
Fire bombs/beams are a great distraction and make it much easier to take larger ships. Beware of auto-fire though.
Try to maintain a large crew to be able to deal with fires and invaders in your own ship.
When boarding AI ships, you need teleporter level 2 to (or possibly Rock boarding crew) to bring your guys back before they asphyxiate.
The best way to board AI ships though is through a boarding drone since they don't need oxygen and the AI ship cannot kill it.
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This message was edited 1 time. Last update was at 05/19/2018 15:32:38