Good Luck with that, every MMO or roleplaying game in general, from loot drops to auto attack, is based off of RNG. e.g whether a hit lands or misses is a RNG, modified by your accuracy stat, hence why there are "soft caps" of accuracy where your modifier negates the low end of the RNG, making it impossible to miss. D&D, Everquest, Warcraft, FFXI, and now FFXIV all follow this formula, hell even the pen and paper rpgs did. Though I agree it's not perfect, it's like they say about democracy; it's the best system we have so far.