ArenaNet:Guild Wars 2 suggestions/Immunities and vulnerabilities relative to attributes

(Discussion)
Allow both monsters and characters to have immunity or vulnerability in form of relative modifier to attributes. For example if elementalist with fire attribute 20 cast spell to monster with immunity to fire 5, the attack will have effect at attribute level 15. Damage reduction per damage type should be reworked to use similar mechanism - instead monsters with double damage from fire attacks lets have monsters with for example fire vulnerability -10. Players can obtain immunities / vulnerabilities via skills or equipment. There can be also immunities or vulnerabilities with conditions like "+10 immunity to all AoE spells" or "-5 vulnerability to all touch skills".


 * Why this is a good idea
 * This change easily fits in present game mechanics and by replacing damage reduction per damage type even makes game rules simpler
 * In contrary to simple damage reduction per damage type this affect also other effects like hex or condition duration thus makes game more diverse.
 * Effects of some skill can stop to grow after some attribute value but still it would have sense to have higher associated attribute because foes can have immunity.
 * In PvE forces more to change builds and strategies according monster type
 * If PvP over-used builds will soon face other players wear appropriate immunities, therefore make game more auto-balancing.


 * Why it may not work out
 * There is a lots of different attributes. If effective using of this rules would require often many different immunities or vulnerabilities on creatures it forces players to spend too much time studying monsters description.
 * Can make some areas or quests too easy for one profession and too hard for other.
 * Can make some areas too easy with specific equipment (if most monsters uses skills tied to the same attribute).