V.T.
My daughter did better when I let her drink it herself. I put it in measuring cup and she drinks it herself. She likes the independence of doing it on her own. Also, I don't know of a cartoon character, but they do make an elephant dispenser that might help, but I think you are on to something with a cartoon character teaching about medicine.
When my daughter doesn't like the medicine, I put it in full strength orange juice. For some reason she will only take it if hidden in orange juice.