You loose reputation, if someone sees you stealing.
Karma isn't used for stealing / in general, right now.
Well then it should be defined somehow what it means "if someone sees me stealing". If that means players/guards need just to look at my direction then whats the point of stealing? I got 260 stealing skill and Pickpocket perk. I can steal pretty much anything no matter the size/weight of an item and stealing window gets closed rarely when I fail.
But when I steal items listed above in a row from brahmin and no one says a thing, nor guards or players, then I assume no one noticed. Whats the point of stealing when you get magically flagged every time you use the skill no matte what... its just dumb. And I don't know if what you say about karma is current change or its been there from the beginning of this season. But I can assure you, that -karma was there some 3 days ago and it was based on amount of items you stolen and numbers of -karma went sky
high deep. For one successful thievery from this particular brahmin and I'm forced to avoid NCR to the rest of this season because its at -5700 karma point right now and there is no way how I can get it back to neutral.
Make stealing more useful but also more risky when it comes to bigger objects like guns/armors/materials. Also some "disturbance" check could be done when you try to steal from people in crowds (10 hexes radius). More people running around = more sneak bonus for stealing purposes = stealing unnoticed with more ease. Simply stealing skill should be based on thief's agility (not the one from special) and his inventions. If someone just masses points up to the max and then tries to rob alone standing NPC/player then he will fail more or less every-time. But when one focus on his pray and waits for his moment he should not have any "moral" barricades standing in his way of making fortune (aka insane karma drop).