kind of a stupid question probably, but when a monster is weak to an element, how important is this compared to raw weapon damage?
Rule of thumb: for slow weapons such as Great Swords, you want to prioritize Raw over Element (Elements here are a bonus). For fast weapons such as Dual blades, it's Element over Raw (doesn't mean than Raw isn't important, just that most of your damages will come from attacking a monster with an element he is weak to). Bow relies heavily on Element damages to do any damage at all.
Slow weapons: Great sword, Hammer, Switch Axe, Heavy Bowgun.
Middle ground: Insect Glaive, Hunting Horn, Long Sword, GunLance, Charge Blade.
Fast weapons: Sword and Shield, Dual Blades, Lance,
Bow, Light Bowgun (elemental shots rapid fire).
Do note that the above list is just my opinion, and that other hunters may think otherwise.