I understand that different weapons work in different ways. However, I still cannot see a reason to not just use the strongest weapon available for every party member. For me currently, this means running around with the latest Bow or Spear.

Even if I were to choose to use 1H weapons with shields, why not just use the same strongest 1H weapon for everyone? Beyond that, for certain battles, it seems that you are more likely to be hurt by using a variety of weapons.

For example:
(SPOILER)When fighting the bird before the tomb... it seems like using nothing but ranged weapons would be the the best option. Why even use any other weapon than the Killer Bow for everyone?