tayrell can also farm Campaign ( not the fastest ) but pretty reliable. my suggestions in order :
I would first go Tayrell, Apothecary for your general progression.
Skullcrusher for clan boss and fireknight. And mausoleum Mage for dungeons, arena and also Clan boss.
Jareg is kind of redundant in CB with tayrell already there but can still help in dugeons liek dragon, or even in cb as additional ally protection in conjunction with Skullcrusher , will serve also as backup attack down.
Psylar is great in dungeons and faction wars, and even in arena but I'd leave her for last as she can still work pretty well at level 50 with good enough gear.
Best of luck.