She's a good villain in the original but I definitely prefer her in the third movie. This one scene from the movie should explain why and it's a scene where she doesn't use magic.

Lady Tremaine: You look confused dear.

Cinderella: How could the slipper have fit Anastasia? I danced with the prince! That was my slipper! Here, I have the other one. I'm the one he's looking for!

Lady Tremaine: You may have danced with him, you may have even thought it was love. But the slipper fits Anastasia and that's who he's marrying. *Takes slipper away* Whatever you think happened last night... was a dream. *Drops the slipper down the staircase and breaks it* I don't care where you go or what you do, but you stay away from the palace... stay away from the prince! *Walks down staircase* Oh and clean up that broken glass.....

Cold as ice...

She seemed a bit less real in the third movie.

I agree with KataraLover.