NPC shops i agree with, but i'd do them in a different way, requiring a contract with the city to pay a tax, and only NPCs that can sell stuff, are hired clerks from a office inside the city, and if killed, the shop keeper merc's gear would be looted by any guards that are close enough, as for being pick pocketable, if they've got protection from the guards due to the contract with the city, than i don't think boosting the spotting power of them would be to bad, since they'd be standing watch over items, not doing other things. but all and all, a non-combat NPC like that could be handy for a supplie master for a gang base as well. and also setting up the prices for different types of items, and perhaps having a "faction chip" which would act like a means of getting gear from the trader without spending pure caps, wouldn't amuse huge PvP gangs, but it'd be fun for the lower level groups.
gathering resources i do agree with, but not crafting, just basic farming of resources, and only if given the right tools. and they'd work with a slower time out. also, as a "mine camping" work around, you could make it against the law to have slaves work there due to the NCR rangers. thus not allowing them to farm some protected mines, but still able to farm unguarded ones, and maybe having to buy a contract for areas like the San Fran mine. and maybe for the junk town mine.
as for merc slavers, i'd agree that a option to allow them to not kill a enemy could work, but other wise thats as far as i'd say that should go, since that'd be a bit to easy.
i missed a few points, but its late here.. >,..,> so any new suggestions i'd have liked to add, are already written down in this topic.
http://fodev.net/forum/index.php?topic=4631.msg42324#msg42324anyway, cheers folks.
-Ulrek-