Awesome prototype! Personally i think the growth will have to be slowed a bit but I can understand playing with the limits for prototyping purposes. Also if I could say adjusting the characters movement speed as they grow would make movement much less frustrating (it kinda feels like those dreams where you can't move so it might turn off some players). Maybe movement can increase on like a negative slope where the bigger you are the more your size impedes you, while still accounting for the bigger gait. Beyond that this looks super fun!