I think the NPC's Madora, Jahan and Bairdotr are annnoying, Wolgraff much less so.
No and yes, it isnt easy all the time, Spiders I really hate they seem like they cheat and bosses can be problematic, also I have only 3 in the party, sometimes I feel pretty outnumbered and if even one is stunned or frozen or downed thats 33% of all capability out.
Yeah Boulder bash should do more crushing damage and no poison damage at all, I like it because it is one of the few bashing spells, most enema's have little resistance to it, but yeah that poison is a real downside or I would usee it more.
Tank ( Knight) and Mage (air and water colleges most versatile, even though fireball is my favorite overall spell) my faves in this game, but you really need a Ranger/Archer because Tanks have very little ranged capability I kind of offset that by giving him all the attack scrolls, heck I sell all the other scrolls anyway.