speech isn't as useful as it was in the old games, there is a speech check but a lot of people cheese the system and save reload until the chances fall in their favor.. and while charisma helps for bartering.. you can just simply.. trade all the stuff you need.. then slaughter your trade target to get the key to his/her supply locker
. Its all about the perception/intel/agi this time around.
I went small guns and sneak then lockpick.. and you're pretty much an unstoppable killing machine since sneaking crits are insta kills usuallly or at least 50% of the target's hp.