My take is have as much junk as you want. Just have to pay for a place to store the stuff, and risk getting it stolen. Carry as much as you want but there are penalties for the weight. Carry to much and it starts to drag down your Reflexes. Backpacks and duffle bags are good for carrying stuff. Just be sure to have accurate weights. Ammo is heavy. If NPCs are going to react different ways to the way PCs are dressed maybe that could be extended to carried items. Try explaining to the cops why you are carrying 3 AKs splattered with blood.
I do like the idea of showing weapons. Have the holster you by determine where it goes. If you want dual shoulder holsters that is what you buy, and that determines where they go. A hip holster goes on your belt. A drop holster winds up on your thigh. A paddle holster for the small of your back.
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Couldn't agree more on the idea of how NPC's react to the player being based on what they see. May be worth bearing the 'Big Brother' aspect as well, becase I am sure that almost everything will be covered in camera's in nicer area's, less so on the other end of the scale. The police should be aware if your carrying or using illegal weaponry based on the security level of the area your operating in.
As for holsters; spot on. Combine that with a locational inventory system and you can put holsters and pouches wherever you want on your person, and then place weapons in those holsters, thus giving quick access to them and organising them for quick equiping. Of course, having 2 hands, dual weilding pistols and some SMG's should be available.Get enough chrome and maybe even smaller AR's could be dual weilded. Obviously, if all your holsters are right handed, your just not going to be able to grab a holstered weapon for your left hand.
I don't imagine anyone could carry more than 3 weapons on slings and use them effectively. Maybe 4 if they were beefy. Then again, different weapons on slings will take up different amounts of space. The reflex penalties could come in at this point also. It's not just the weight of what your carrying, but bulk too. If I was packing 4 handguns and 2 SMG's in holsters as well as carrying carrying a Sniper Rifle, 2 Assault Rifles and a Shotgun on slings, (not to mention several sheathed knives and a few blocks of C6,) not only would I be weighed down by all those weapons, I would not have much room to carry ammo, nor would I be able to efficiently equip those weapons because there would be so many others in the way. I would also look ridiculous. Afterall, I would have no room for my RPG!
That said, I think players should have the option to become walking armories. I am also in favour of letting players learn the hard way. (I play EVE Online. For anyone who has not experienced it's unique learning curve, here is an accurate diagram
