It's time for her to retire, and make money through movie appearances, commercials, commentating and/or advertising. Maybe another shot in the octagon against a lower tier fighter to build back her reputation again, but no way a title fight. Like you other guys said, the division changed. Better female fighters are coming in.
That said, I def wouldn't mind seeing Meisha Tate again. While she's not the best, she has the looks and right attitude for the sport. Rousey's attitude was horrible, especially when she fought Holms. She didn't even touch gloves before that fight, clear sign of disrespect.