It seems to me that the biggest balancing is when a given weapon is heirloomed. This is the especially case with the steel pick, which has had a couple threads primarily about its MW form. My suggestion, as a remedy for most of these balance issues, is to remove any increases to speed given by heirlooming a weapon. For many weapons balancing issues stem from MW weapons crossing that fine line between fast and too fast.
What do other folks think? I'd be happy with improvements for only weapon damage and weight.