Has there been any word or guesses on how colosseum will be in this game? Pvp?

Also, is there anything like a tier/priority list for the maidens? I've gotten several maidens from free rolls, quests, the log in and getting closer to getting the event girls but after that, I'm not sure who to prioritize leveling and gearing up that'll help the most and hopefully help in colosseum. I'm sure rarity is important but it seems some of the legendary girls have terrible skills? Heet hurts herself to use her skill and Micah's can miss according to what I've read in this topic. I don't have all the girls but listing all of them is fine for future references if anyone has any opinions on them.