So unfortunately I don't own either so I can't be much help there but just aesthetically speaking my personal opinion is the kelly doesn't bring much to the table. It is nice for stacking, yes, but not for that price point.
I would say either the Bulgari or panthere. But realistically if you want to wear it all the time like your other ones the Bulgari would blend in and compliment everything seamlessly. The panthere needs to be displayed by itself. Maybe I'm biased toward cartier but it's such a stunning piece that needs to be showcased and not stacked.
The Bulgari piece is also beautiful but it works well for stacking! And i don't think mixing white gold with your current yellow gold should be a problem. It could work very nicely together and it won't be that problematic anyway since the diamonds on both bracelets have a white element to them