Jurlee or estien

Ok so I may have spelled the names wrong. please forgive me for this. My point is I am looking to get a 6 star mage. my main focus is boss hunting. I have heard that estien has Really god crit with single target, at the same time jurlee is amazing single target as well, basically a ree. Anyways I am looking for information from players who have had both or have one and had the other. The more details the more interested I am in this please. Yes I have checked the wiki. The reason why I am asking for help is because Either I am spending a ton of resources in spin tickets during the events jurlee is up or I am spending a TON in courage.

I am intrested in Boss hunting, more than PVP so please i do not need information on how great tarxus is or whatnot. Thank you for your time.

Juralee is stronger all around, Einstina is the weakest 6* mage just as Roxy is the weakest 6* warrior.
The Destiny Spin heroes are always top tier, The Queen being overly tanky, Aelis being an amazing hunter than can kill the back row easily, and Juralee being a single target nuker.

Rathim and Oph, the 6*s you get pieces for when you summon (when lucky) are middle tier 6*s, being far superior to 5* and just a little under your starter when leveled.

Well that answers my question, and I am going to continue to spend my courage gems on chests to get kings gear then. Thank you and I will be saving for spins. atm i have 5 jurlee, I know that does not seem like much but its a start.