There are a few rules I follow-with a statement necklace and you have pierced ears-wear small earrings, gold, silver, brass, bronze, shiny silver or whatever metal is the base of the statement piece. like if there is a chain, the metal of the clasp, etc. If you wear long dangly earrings, either no necklace, or something long, like a long chain with pendant. With a statement necklace it looks best to wear something that fills in the neckline -like v neck or a rounded scoup neckline. If you want to showcase a vintage piece, or a unique piece, then do not wear anything like earring to detract from it. wear small hoops, studs, or such.
sometimes matchy looks great, but not in the sense of something purchased as a set. One matchy I do is a sort of set I made. Fresh water pearl earrings -just 1 pearl on a dangly 1 inch chain, with a long string of fresh water pearls, with abalone shell, and wire wrap with pearl. get loads of compliments on it. This combo is worn with things like black, navy, or other plain dark tops.