As for magic items being possibly useful, hrm, I guess you could make certain insane mods available to magic items only. Not sure if it would be a good thing though.
I was thinking more along the lines of, it's more common to find a magic staff with something like: +2 wizard +3 slow time(just an example) than finding a non-magic item(rares, uniques, sets) with stats like: +2 wizard +3 slow time +10fcr +15 resitances(ect...)
So you would basically use those magic items until you found a better one (rare, uniquem set) to replace it. Maybe for your specific build finding a staff with those mods is really rare, so that magic one holds more value.
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Ah ok, that makes a lot of sense.