Eh... focus effects are pretty critical for a caster. Though, the poorly thought out server augment negates that here. Typically, you need to be hunting for the highest fire / ice / magic direct damage focus items as a wizard. VT / Plane of Time focus would be very meaningful. But, you can just save 15k plat and buy that server aug that has a bunch of great effects. One of which is +45% spell damage (all types). So yea, focus item gear is now meaningless for them.
I have a 3 box team of wizzies I made. They were incredibly fun and 1 shot up to Kunark bosses (not VP), but as the xpacs get deeper the HP scaling is less. Even 3x wizzies aren't taking down Velious bosses. By the time they were in PoTime, you end up blowing through multiple mana bars and have to deal with zoning out to get out of combat to med. Then you have the AE mana drain bosses that make your wizard almost entirely useless without a bard or 500 worn resists.
TLDR: Wiz are fun as hell here in the early game, but have a ton of limitations later on that other classes like zerker, rogue, monk do not deal with.