What are good defensive weapons in elite dangerous?
Lasers are good against shielded enemies but a multicannon will do far better against hull. I would go with one gimballed pulse laser and a gimballed multicannon, just fire both constantly. You're only going to be fighting if someone attacks you first, so you shouldn't need to worry about running out of ammo too much.
Chaff is also very good as it will make gimballed weapons miss when targeting you, which keeps you alive longer.