All fury runes did was make your adrenaline charges last longer... for example if you whacked someone, then stood around for a bit, your adrenal skills would stay lit up a little bit longer. Not sure how you get unbalanced out of that. *shrugs*
combine that (runes) with battle rage - or even berzerker stance and u get warrior who can't empty adrenalin...
i'd like that but, it'll make warrior too powerfull; i think it's reasonably removed