60 rearguard sergeant if you're having trouble surviving. try to get speed and accuracy on her. 100 crit rate *if you can*, but focus on speed/acc first. i think she'll be better than apothacary.
60 coldheart eventually, she's great in a lot of lvl 20 dungeons.
never 60 warpriest or chaplain, waste of resources. i wouldn't even keep building them.
ruel you can wait on, he'll be hard for you to use with the rest of your roster. if you ever get an aoe hex champ, then build ruel as a nuker.
faceless is pretty strong and can be used in faction wars as well as other places. he's a strong hitter if built right, so consider leveling him after rearguard/coldheart.
high katune is fine at 50. hopefully you pull another reviver sometime in the near future.
apothacary is fine at 50 too in my opinion. most support champs don't need to be 60 early on, especially since you don't have the banners to stick on them probably.
the starter champs are all good at 60. elhain or athel you could bring up and put in lifesteal gear, both will do well for you in different dungeons.
a good chunk of those rares i'd use as food and never gear. the champs used for fusions you can stick in your vault for later leveling/fusing.