I have mixed feelings, because I could see potential in the idea of a series. Maybe something built around the search for the Hatter’s lost wife, with him traveling through many realms, happening contemporaneously with the events in SB/OUAT timeline.
While Stan was great in the role, the switch to a new actor could be even part of the storyline. Either the hatter transforms his body somehow or is altered in some way, or the hat is literally passed to someone else who becomes the Hatter (and so the lost wife storyline might not really work then) but there’s an explanation beyond the original actor couldn’t continue.
“If I had a world of my own, everything would be nonsense. Nothing would be what it is, because everything would be what it isn't. And contrary wise, what is, it wouldn't be. And what it wouldn't be, it would. You see?” -- Lewis Carroll, Alice's Adventures in Wonderland & Through the Looking-Glass