I just glanced at the all the upgradable/customization stuff. So not sure about the balaclava, but there is some options towards your suit, you can change your color of the suit, the color of the lights and the color of your night vision goggles. As far as I can tell you always have to pick the larger weapon, even if you don't have one I believe Sam will just automatically throw one on his back from a knocked out enemy. Oh yeah you can definitely upgrade weapons. Upgrading is a huge part of the game. Just glancing at the menus, it looks like it'll be pretty overwhelming right away. You can also upgrade the Paladin with some pretty sweet upgrades.
I know a lot of places have kinda bashed the game for its graphics but when you're in mission, I think its a pretty damn good looking game especially the day time scenes. I've been trying to do a fully ghost playthrough and while that already didn't fully work out for me, I've at least stuck to the panther and at the end of every level they award you much more highly for going ghost and panther rather than assault. Ghost you get a x150 whereas Assault its just a x75. So I thought that was cool that they split it up like that. The level design is the real show stealer in this game, there are so many different paths you can take and it feels like they're finally able to cater the hardcore stealth as well as the people who just want to shoot everyone up. I'm liking Eric Johnson as Sam especially when he is talking to Sam or when he gets a bit aggrevated. When he is normally talking or giving orders, he kind of sounds bored, I think that is just because of the deep voice though.
I've only done a few missions but this is easily my favorite Splinter Cell so far.
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