QUOTE (Draco18s @ May 17 2013, 02:36 PM)

I'm not saying that a high charisma shouldn't help, it's more a problem of "being big and scary not helping." Which doesn't happen in SR (because we have things like notoriety and modifiers for brandishing weapons). In D&D 3.5 the only way for a barbarian to be scary was to also be diplomatic.
Uh... in 3.5 you got a +4 modifier to intimidate checks for every size bigger than your opponent you are. It may not come up very frequently, but it is there. Also Barbarians had Intimidate as a class skill, but not diplomacy. Attributes don't play as large of a role in skill checks in 3.5 as they do in shadowrun, for most skills you're looking at a +1-3 bonus from attribute, but as high as +23 from skill in a skill you are trained in, and even higher if you focus in it.
Also you mentioned charisma helping "some other" barbarian class abilities. Unless you're referring to other skills (which hardly count as abilities), then that is blatantly untrue. Even if you are referring to skills, your only other cha based option is Handle Animal, hardly a go-to ability for all barbarians, or one that is needed for the archtype to function.
I wouldn't consider a barbarian with even a +3 diplomacy mod very diplomatic (and most barbarians won't even be that high, maybe a +1 at the outside), but I would consider a barbarian with a +25 or so intimidate modifier very intimidating. So I really don't see what your complaint here is that can't be applied to literally any system that uses attributes as a component of their skill system, and most of them with far more truth to it than yours.
Anyway, on the topic, I could see the limits working, but... yeah having Social/Physical/Mental seems like a really stupid and arbitrary setup. The problem of the big strong guy having a higher limit at agility based things is already shown. What would make more sense is just making the linked attribute your limit. It gets rid of the need for an extra notation, removes 3 extra stats off the character sheet, accomplishes the same intended person, and makes everything make far more sense.
I do have other reservations/potential problems, but I need to see more before I can say for sure whether they're there. There's been concerns voiced elsewhere about a pistol being better for sniping and a sniper rifle being better in close combat, due to the accuracy limits, but if in the combat section they handle penalties with threshold modifiers instead of dice pool modifiers, that complaint is untrue. I can also see some wonkiness in the teamwork test rules depending on what they allow to be a teamwork test. (Example: Imagine the group stealthing through a building as a teamwork test. Your group is actually stealthier for having an extra guy along who may or may not have any sort of training, than if it was just one guy alone). I also have reservations about the extended test rules, but that's mostly because those rules are exactly the same as SR4A, and I don't like how they play out there either.