Smarter Gate keepers

[Hiztaar]

Hi !

I'm playing this very fun and immersive game for a week. So I came here wondering why do my NPC have to stand unprotected with my door open while I spent a fortune building huge walls ? Why can't they simply unlock and open the door to merchants and friendlies and keep it closed to hostiles ?

I dunno if it's on the pipe but it would be a great improvement !