I am not even sure I'm going to want to watch the show if she's not on it. Fish is the best character on there by a mile. From EW:
Is this the end for Fish Mooney? Gotham will have a second season, presumably because the show needs more time to fit in Young Mr. Freeze and Kid Croc, but Jada Pinkett Smith may not continue with the series in the future. Pinkett Smith appeared on Live With Kelly and Michael, and after a discussion of Mooney’s undeniable badassery, Ripa asked the star whether she’ll be back next year.
“I don’t think so, no. I signed for a year and the year is up,” Pinkett Smith said. “But there are some great things coming ahead on Gotham, believe you me. There’s a lot of good stuff coming.”
That seems pretty definitive that Pinkett Smith will not continue as a regular, but it’s unclear what it means for the gangster boss she plays. Will Mooney die off, or just take an extended break from Gotham City? Pinkett Smith certainly left the door open to possible cameo appearances: “She could show up anywhere, you never know!”