Mythics will be the 2nd easiest just because you will be able to buy the emp items. It may cost you 60 mil but I would much rather farm dynamis for 3 weeks than worry about building 3-10 PW sets. If relic and mythic items came from mobs that people actually killed and there was a chance of them being on the market for less than 20 mil then it would for sure be mythic < relic < emp but the way its set up now its emp < mythic << relic.