Improving Monk and Barbarian only drops would be a good start. Giving them something that just flat out works only for them would be the best itemization fix. Or I guess just improving them all across the board but really, really fix Monk and Barb ones :x
Making STR relevant would be nice too I guess. Something like gaining a % of STR from Vitality, or buffing Barb armor passives to includes some resists, so that you can stop looking for survival gear first and actually do some decent DPs without top of the line 20 million a pop gear. The way it is now you are forced to look for items that have All Resists -> Vit -> Physical Resist -> %dmg reduction -> Block%/Life on Hit/etc. all of which come before STR which is supposed to be your main stat.
Getting one item with good numbers in ALL of those is nigh impossible without some serious investment.