Help me with something understanding servants.

For base defense servants, the only thing that matters is their type right? They will use all the same skills as they do when you encounter them in the field and be at whatever gear level you equip them with.
For prisoners, the only thing that matters is the %?
For missions, the type matters for sending them on missions but only really if they underlevel the area? If you gear them beyond it then that lets you do the missions without worry of fail anyway.
I haven't had any of my servants get injured yet, how does that work? What happens when they do and can you heal them or do they die.

Also I made the mistake of putting a 96% rogue in a coffin, I misremembered a video I watched and thought I could put them in the prison if I wanted to at anytime, but I guess I was mistaken.

Also, if you are raided and a coffin is destroyed while its converting a servant, does it delete the servant its converting or what?