The Tome lvls up fast and with recharging equipment you got quite some attacks. The main target ist not killing enemies with the spells but to make it easier, i mainly use searing light in the beginning - just for the tougher enemies. Later on i use sunray to blind ranged enemies and close the gap to them. Both spelly only cost 1 charge. Later i used prismatic image and healed my buddy with hollowed ground and bless. Worked fine. So yes it depends on the dome, but some of the spells there are really usefull especially at early lvls.
No matter what char you play - it mainly depends on some decent luck to find armor, weapon and rings. Most important thing is to find decent armor asap. Ring of evasion and elemental are also really helpfull. The abilities of the chars are a nice add on and make it interesting. The only char that is less depended on armor is the Mage.
Ascended as well today :) Supporting works fine, yes but beside prisamtic image and the ghost there is not much to support right now...im praying for sellswords that can be hired at the shops :)