I melee in pc and put points on mage and have got from about 75-93 mage from doing it, it is easier in my opinion to melee but if you can afford the runes i would mage to get even more exp out of it.
best defence would be to use torags chest and legs, and replace the obby shield with a rune defender as that gives good defence and great attack bonuses to get a max on a whip to 125+slash bonus(using a warrior helm aswell). You could also replace the berserker items with warriors for accuracy depending on your stats, which ever needs the greater boost.
i haven't finished the quest yet but i found kamil the 154 ice man, the ahrdest part so far he owned me 5 times, didn't die once managed to tele away, but he kept just hitin me high every time
I put on all 15%+ prayers then dds special which ever portal i run to normally random, mainly yellow though as i seem to hit it more often, after dds special is gone, i use either d long or d scim, with my rune defender \