I understand what the OP is trying to say, but I strongly disagree with the solution suggested.
For how I see it, the last thing this game needs is EVEN MORE wild variations in numbers.
Once again I think the Baldur's Gate model should be the one to follow: few distinct tiers in quality, with no level scaling or requirement, not too far apart in terms of stats to prevent insane variations, but with a broad range of secondary special abilities to make each one of the top quality items feel unique and valuable.