Feedback unique item generation, only on normal act 1-3 bases and no advanced/expert?

There currently seems to be a huge oversight with the way uniques are generating. Each unique can only exist on a single base currently

i.e. Death's Harp Dualstring Bow

But there is no Death's Harp Advanced or Expert Dualstring Bow.

This makes almost every unique really bad because the base values are almost 40 levels under those in endgame.

In the same example a normal death's harp has a damage range of 16-31 while an expert version would have 39-73. This comes out to be ~2.4x more damage. This goes for every unique basically making them useless beyond levelling in normal act 1-3.

Weapons are hit the hardest by this but the same goes for base evasion and armour values making any rare far superior in the base stats that they provide.

Another issue:
Most uniques that drop are basically useless for the character I play. I think uniques could be categorized and related to the different classes and you could have a significantly higher chance to get one that fits your class. The same unique could fit multiple classes. In addition to that the game could recognize if you play something unusual for a while (like using bow skills as sorceress) and then prime you for that kind of loot as well.