Rosalind Chao had a recurring role on Star Trek: The Next Generation as Keiko O'Brien, the wife of Chief Miles O'Brien . When Meaney moved to Star Trek: Deep Space Nine, so did Chao. She actually appeared in more episodes on Deep Space Nine than she did in The Next Generation, but that didn't give her much more to do.
Her character was a minor one, and there were no standout stories for her, with the exception of Deep Space Nine's "The Assignment" when Keiko was possessed by a Pah-wraith who then tried to convince O'Brien to attack the Prophets. But had she gotten the role she was the actual favorite for, things might have turned out quite differently for her.
According to an April 13, 1987 memo to John Pike from John Ferraro provided by Letters of Note, regarding the casting of Star Trek: The Next Generation characters, Chao was in the running as the character of Lt. Tasha Yar, the chief of security aboard the Enterprise. And not only that, she seemed to be the favorite for the part.
How different would The Next Generation have been with Chao as Tasha Yar? She wasn't given much to work with as Keiko O'Brien, but those of us who've seen her take on the role of Rose in The Joy Luck Club know she was capable of so much more.
Denise Crosby didn't stay in the role very long because she didn't like what the producers were doing with the character. But Chao stayed with Keiko O'Brien even though it was a bit part. So odds are good she would have remained in the role she would have made her own. Chao was never well-liked as Chief O'Brien's wife, but, as evidenced in her other acting roles, she has the talent and would have been a Yar who potentially wouldn't have been killed by black slime.