You are probably wondering exactly what this means.
I think it would be useful to add another dimension to identify an item. Currently, the QL level really equates to the "level" of the item. Since it is probably too difficult to change this, just leave the QL as is, and add a second metrix to the item to itentify it's real "effectiveness/quality".
Why?
This would add more variety to items, and allow certain items of the same QL to be more valuable. For example, there could be two rare, level 200 items. One could be of average quality, and the other could be of perfect quality. Obviously, the higher the quality of the item, the better its bonuses would be, above and beyond what is typically received.
Just an idea to add more variety and value to items.