Quite a few classes can use the bow and any class that can throw can use the shuriken. You don't strictly need to use them at all and you can opt to use one or both. I'd recommend having at least one designated character that can use one or the other (when it's useful that is). But assuming everyone uses a tank then that's covered
But given rangers are best at using bows, for example, then they'd be the most desirable in that case. You just don't need one.
We're monitoring the difficulty as we go. We've been looking at logs and will be making some initial adjustments soon. I'm going to make a post about it hopefully tomorrow so watch out for that.
We might make some further changes to how difficult the npcs are but we've had no specific feedback yet from anyone on how difficult the events or npcs are (until now).
Ideally, once we've made our first adjustments, see if you can actually complete it first and give us some specific feedback as you go (name the task and npc if you can if you find it difficult). Please use the petition forum for now to avoid spoilers. We can get a thread going and keep updating it.
We're mainly interested in how difficult you find it though. Not just npcs either, tasks and other aspects.
Thanks!