Hi, I checked your profile, but you have several projects there. I couldn't figure out which game these images are from.
It would be nice if you could provide a brief description of your game or a link to the project.
In general, I can say:
The characters are interesting, although the boy looks a bit old. Maybe that's the author's intention, idk.
Personally, I would emphasize some of the character's unique features when drawing them, so they would better reflect their personality (for example: smart - a big head, cunning - a rat-like face, etc.). Right now, all the characters seem to be made from the same template.
In any case, you don't use AI, you draw everything by hand, so respect to you and good luck with the project.