Honestly, I think it'd be neat as long as it was regulated and created in a sense that wouldn't make it able to be abused. Various fantasy settings include firearms, and both firearms and weapons such as bows and crossbows have their strengths and weaknesses. LotC has been getting quite dull for me, so because of that I'm not afraid of change. If an idea such as this is attempted to be made integrated into the game and it doesn't work out how it was planned, then remove it. I think it's worth a shot, and it would definitely bring some very interesting roleplay.