I would find it nice if we could have the ability to recruit AI ships in career mode to team up with us.
You would probably need either a decent amount of money or a good reputation with a faction in order to get one of their ships to team up with you. We already have time limited missions so I believe it would be possible to implement a timer after which those ships would leave you.
You get refunded a part of what you paid if the ship you recruited returns (mostly) in one piece, otherwise you have to pay the extra fee as compensation for the lost ship and resources.
I think that's about it? Let me know what you think.