My bad I totally misread that.
Sewers is garbage. There’s not really good eq upgrades in upper sewers IIRC, and they make a pretty big difference. Particularly in rendering your need for healing largely irrelevant (you’ll still be hitting up temples for the occasional de-statusing or even a raise). Also there’s a ton of nice gear upgrades to be found Cat 1, if you don’t recall. They’ll render the front line nigh-invincible in no time. There’s a ton of fixed encounters to exploit right by the entrance.
Multi WASTs will kill most wights and ghouls but Dragon’s breath is better. And pretty soon, you’ll only rarely stop by the temple to correct the occasional hit that lands on the front line.