Creating something new So currently I'm trying to "modify" a version of DnD to an extent where a friend of mine will play it with us. He is absolutely no fan of this whole genre, so we decided that I try to modify it to a different universe. Supernatural (don't even question it). So far so good, but I'm having issus with balancing weapons, enemies and creating a custom character sheet that fits the scenario. Does anybody have experience with this and might provide me with some tips and tricks?! 
Note: The version I try to modify is "DS Aventurien", basically a simplyfied ruleset with other small adjustments.