Not sure if this area is still being looked at, but I would like to see some gem style necklaces that would be higher up than the current ones (so they are above the "V" and "U" neck lines of shirts). They can use the same layers and color options as the current necklaces so it shouldn't be too hard to make them.
Some examples of the necklace type I'm thinking of:
(sorry for the varied sizes, they are cropped from different screenshots from games, programs, and AI art)