In another topic I've said that magic users in RM are too powerful compared to other characters, here I'll try to explain why.
The answer, in brief, would be that they've too many options at their disposal. Spell users can do anything non users can do, better... and then some.
While at the beginning a user is more or less at the same "power level" of a non user (sure, a 1st level fighter will be more efficient in combat than a 1st level mage, but the magician have other strenghts, for example lores or skills like read runes, not counting his low level spells), as the user advances he gets more and more options, while the non user strenghts remain the same. Even worse, the options he gains are often far more powerful versions than those of non spell users or are even completely different options, which non users simply cannot obtain.
Think about it, a high level user can:
- fight better than any fighter, with his mass-destruction spells like fireball or with single powerful spells like dark slumbers
- stalk and hide better than any thief, with invisibility, shadows, and other spells
- influence people better than any influence skill, with Charm Kind, Suggestion, etc
- heal wounds instantly and better than any healing skills
- solve mysteries in no time with divination spells
- be better at noticing and analyzing things than any non user
- move around istantly, anywhere, even in places where non user simply cannot go, like the sky
- speak and understand any language, without buying ranks for it
- and many other things
Sure, he must learn the right spell lists and develop PPs, but non users still have to develop their own skills, which cannot compete with spells, so it's not really a big disvantage.
Another problem is that often the only thing that can beat magic is magic alone. On the other topic I've said that a simple spell like Presence would make sure that a SU will be never ambushed. Then someone replied that a Unpresence item would solve the matter. The problem is that Unpresence is another spell, and that means that a non magi using character would have no means, by himself, to solve the problem.
Non users have to rely on external (magical) aid to have a chance to compete with users, while the casters can do all their work by themselves.
Now, the big question:
Why do you think it is supposed to be balanced? I have always viewed high level casters as much more dangerous than the warriors. It takes more to get there but........
Because it's more fun. How fun is being an expert swordsman if the party spell caster can snap his fingers and Absolve any enemy? How fun is being a master thief is the party spell user can make himself invisible, teleport inside the castle and teleport himself and all the king's treasury out? How fun is spending levels to develop your awareness and lore skills if the party seer can solve any mystery and find anything/anyone without even having to leave his seat?
I'm not saying that magic should lose its versatility, but I think that, should a revision be done, magic should be a little toned down and mundane skills powered up a little bit. IMHO non users should be able to compete with spell casters without having to use magical aids, at least in their field.