Questions about CharactersFollow

Hello, all how are you? I hope to be getting my copy of the game in couple of days and untile then I had a few questions, about the aspects of certain characters. First how bad is the creatures resisting mage spells period, and at higher levels? I mean by higher levels where I would be say 40 and the creatures 40-45. Not them being 10 levels higher then me. Also how are the alliance and horde in balance of quests, and gear? Does one have a real quest advantage over the other? I have heard some games would seem to cater to either the good guys or bad guys. I am torn between either a undead/human mage who does alchemy, or a dwarven warrior who smiths. I would love to play and roleplay either one. I choose those races for their roleplay aspect and racial traits. What I choose really comes down to how bad mages have it trying to get their spells to land or not. So if anyone could help me on this topic it would be much appreciated