i have plenty of experience with dnd and role playing game in general, pnp or on computer.
i've been able to kill that wizard only because on normal there's no friendly fire.
I guess you started a new game then without importing from the OC? So, no equip and a pretty empty spellbook? Sounds like a learn to play problem though, even Safya alone should be able to handle everything, when you get the spirit shaman and cleric companions it's just roflstomping.
Remember, Safiya is a transmuter (she gets +5 on spell DC for transmutation spells) so just have her memorize lots of disintegrate, empowered disintegrate etc. Have her learn Finger of Death and Wail of the Banshee, get her the INT ring +6 from the vendor in the city, perhaps pick up some Great INT epic feats. When you get the cleric, slay living, word of faith, implosion etc. It's actually better to use lots of instant death spells, because enemies have massive HP and good saves so a 10d6 fireball won't do much.