Are Rares realy useless?

[TaiDaishar]

I think that a good way to make rares viable yet not all too uber would be to make magic only items be able to appear on items only with 50% quality of the real affix/prefix (aka cruel on rare would be 200-250%) and cleaning the affix pool by not having high level monsters drop items with +1 to light (for example) or having a circlet with firebolt charges and the obvious +% dmg on wands...