Ok just noticed my typo... I meant the 0.12! That's enough for me I think! The 0.08 would do me nicely too though.
Have you considered a yellow or rose gold DBTY if that's the metal colour you would usually wear?
I'm with mills - if you have the rose gold earrings why not go with a rose gold necklace?
My daughter has the silver .07 and it is a nice size and there is also the three diamond drop necklace in rose gold and three diamond "in line" version if you want to save up and have a bit more sparkle.