Currently, weapons with +1 get wc+1, and armor (including shields) with +1 get ac+1. An interesting method of differentiating different playstyles could be:
One-handed weapons and shields continue to receive the traditional wc+1 and ac+1, respectively. Two handed weapons get divided into two camps:
This does leave a final category: two handed defensive “weapons”. This doesn't really exist at the moment, but I could conceive a case or two where a two-handed item gets ac+2 for every +1 on the item. This could happen with a large two-handed shield, and one player in a party could play a “tank” role during a very tough enemy fight.