lvl 92 Inquisitor set on lvl 9 characters
The Inquisitor set has 2 pieces that require only 97 focus to wear and 2 pieces that require 129 focus, while the other pieces require modest amounts of both focus and dexterity. This means that you can, through careful finding of low level armor pieces with built in focus and the addition of a few Eyes of the Winter Widow, you can reach 100+ focus at level 9. If the focus only elements of your Inquisitor set are carefully enchanted to be mostly focus with some dexterity, you can lever your way into the full Inquisitor set at level 9 in any class, giving you 75 % damage reduction (if you've socketed your set with Skulls of Limoany, and who wouldn't?), 8000+ health (Skulls of Riechliu), and the ability to mount endgame weapons and shields (Lovantine Skulls for any needed strength). Some tradeoffs are required for the difference in builtin damage reduction between the two melee classes and the two ranged classes.
Even at level 9, elemental damage is the name of the game with a focus build, and you will have about 400% magic damage and 60% execute change If you dual wield. Dual wield with a Neatherrealm weapon in the off hand you can easily achieve 500% crit damage (Rembren Skulls in both weapons), and you likely have a built in 60+% crit chance from the dexterity enchants and crit chance on the weapons.
This means you can't die except through stupidity through at least level 60 or 70.
Mind you, there is a lot of prep going on to build such a set, but I built Embermages in normal to be the gathering characters, and have an elite NG4 mage wearing this set that has never died.
Now I am playing the other 3 classes, all while wearing endgame gear from level 9 on. All the classes have perfectly viable elemental damage skills that work well with a focus build.