personally i don't feel that way but since RRR is single-player only, then i guess it's ok.

why mage-class shouldn't have high armour ratings other than magically weaved ones?
1. they're ranged fighters who get first hits on enemies.
2. powerful spells that translate to huge damage makes it even easier for spell casters.
3. when u can hit from afar while receiving a few ranged hits, armour isn't essential.
4. since they're pretty far off from the enemies after registering the first hit, they can always run off, guerilla style. that's what sorceress do in diablo 2 & nobody complained.
5. balance. to counter the high attack ratings in mages, compensation will be low armour rating.
6. fun. what is left when u can tank while dish out big damage via area effect spells?

still, my 2 cents.

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