I was thinking of a currency. Have it so you get time bonuses, mutli-kill bonuses, decapitation bonuses, as well as regular money (we could call it scrap or something) for just getting kills. Have armor, weapons, and whatnot all be dependent on money while keeping the skills separate as they are now. It could even be set-up so you have to unlock skills to wield certain weapons or wear certain armor. I wouldn't think weight values would be too hard, just code it so armor type and number decrease overall speed by a certain percentage.