Ok first off, why would you want a bracelet with only 1 FC on it when you can imbue that on an exceptionally crafted one and have a higher property cap? That's just bad crafting and I hope you were just using a bad example.
Jewelry property cap is the same regardless of quality, (exceptional or non-exceptional)
They always equal out to 0/500 when there are 0 mods, However when you imbue an exceptional ring/bracelet, your success chance of adding a mod is increased by a small amount.
Please change -100 luck to reduce item weight for both Imbuing & Unraveling purposes again ! This change only Hurt the game IMO.
There is even less a reason to fight the lower end mobs in shame with this in effect, atleast when it was -100 item weight (which it should) you could use these items to have One mod slightly above the current imbuing cap, and Sacrifice a 5th mod (due to -100 luck counting as a mod) on such ring/bracelet. These items have little to no use now unless you Want luck as a property which only makes these items useful in pvm.
example
Ring (imbued)
Fc 1
Fcr 3
magery +15
Mr 4 (pre-imbued)
luck -100 (pre-imbued) - since -100 item weight, it allows to imbue the highest cap on the other 3 mods (added with imbuing)