Some interesting ideas, but the whole shoot people outside while being safe inside is completely OP. I like the other ideas though, but rather then change some exotics like the Armamentarium I think it'd be best to add new ones in future expansion, boots would be perfect for the bubble movement idea, and there aren't many boots in the game right now so adding new ones would be plenty justified. The bubble definitely shouldn't be very offensive though, it is called defender after all. My idea for an upgrade would be pretty similar to the wizards thing, not in that it does damage or slows people down, but that it reduces visibility. I think an exotic or something that made it so that you couldn't see anything happening inside the bubble from outside would be pretty cool, while still seeing normally inside of it. That way it could really be used for maximum defence, nobody would want to rush into a bubble if they can't see what's inside, and they wouldn't want to use Fist of Havoc or anything like that on it in case it's empty.