No. I wouldn’t be opposed to making it a hard floor on what purge levels the sellsword can spawn. Further, a new player isn’t going to be able to siege the npc castle (they aren’t a noob if they can pull that off). So, npc castle is irrelevant.
I never said there was anything “wrong” with knocking out your first thrall. What I am requesting is an alternative, to increase the options. Everyone is going to approach conan exiles slightly differently, and we are going to find different aspects of the gameplay fun. Some will enjoy not spending money on thralls, knocking them out as a barbarian. Others would rather be merchants and traders, acquiring mercenaries and thralls with coin.
Nothing is lost by opening up the game to complexity and giving multiple routes to do the same thing.
EDIT: This has nothing to do with bombs at all.