Here's a house rule that I'm thinking of adding to my D&D games.
The following items are considered "Heavy" (even if they're not actually actually heavy they require a greater amounts of strength to use effectively). Characters who have less than 13 Strength suffer a penalty of -1 to hit and damage using these items.
Characters with Strength between 3 and 12 would thus be better to choose lighter arms and armour. This seems to fit with the Grey Mouser type characters choosing lighter weapons while the stronger Fafhrd type characters choose the heavier ones.