In my campaign, I do not allow druids the use of the scimitar. It was added to give the druid a decent hth combat weapon, like the sling was for ranged weapons. Plus, the crescent shape was one of the original justifications, i.e. crescent of the moon.
A druid's magic is NOT disrupted by worked metal, otherwise you could prevent one from casting spells by wrapping a chain around his body (even if the chain didn't otherwise affect the druids movements or entrap him). Since the most common weapon/tool of the druid would be a knife, which is almost completely made of worked metal (unless you allow uncommon materials substitutes [crystal, obsidian, etc] to be very common). Thus, in my campaign, druids can use any simple weapon that contains no more worked metal than a dagger. Also, being as the Wild half-elves in my world are the only ones with aboriginal elven blood, they are the ones who have kept the ancient elven tradition of racial bow use (the elves of my world are actually invaders from an alternate world).
So my druids get proficiency with all simple weapons with no more worked metal than a dagger, certain racial weapons which follow those same restrictions, and maybe a few culturally significant "exotic" weapons which fit for hunters, herders, and foresters. Since the crossbow, while a simple weapon without much metal, it is too mechanical to fit for a druid.
Thus, druids are allowed:
dagger, punch dagger (if culturally appropriate), club, sickle, light or heavy mace (stone or like head), shortspear, long spear, quarterstaff, spear, dart, javelin, and sling. This is all of the basic Simple Weapons that qualify with my worked metal restrictions.
skippy
GM of the Cursed Earth