First I'd like to congrat for the great job done on this mod.
The marketplace is very well made, but is, mostly, useless :
For non heirloom item : you have 2 choices. You can sell them directly and loose 50% of the value. Or you can try to sell it on the market with, generally, a slight loss of 10% (and buy another one with a 10% discount).
Why not just loosing 10% automatically instead of loosing 1 week to wait a buyer ?
For heirloom item : you can wait months before trading a common item. Or never, if it's a rare item. Pretty long when you want to change your weapon style. Is it fun ? Nope.
Heirloom points are not overpowered. There is no real justification to wait that long to change your main weapon.
I suggest another system, more simple : to destroy your loomed weapon. That way you get back your loom point and loose your weapon (a kind of malus).
With this simplier system you could try to loom anything more risky, like daggers, shields, boots etc. for a time. And change your armor style more frequently.
Results :
- The game is still balanced
- More fun (major point).
- Marketplace become useless. Except if you want to sell your loom points.