While it might confuse the new people I quite definitly think this would be a good quest although i would put a lvl limit on the 20k xp lamp.lvl 50+ maybe.I would also make the requirements lower but the monsters tougher.The lvl 126s could have barrows armor or maybe 3rd age armor thats better than dragon and i think it comes in all three styles.As for zamoraks servant i think he would do better as the demon that died in the golem.And vannaka could summon slayer monsters during the fight with him but they would be infernal mages.