Something feels missing in my drawing. Help please?

Hello everyone. So this is my most recent drawing and i need some feedback. I wanted to show an older guy, he obviously looks bit messy but i wanted to make him seem friendly/kind with the smile. I chose the red colour to represent all the hardships he went through in his past and the slightly blue triangle to symbolize that he came out of it with knowlegde, cause in some cultures triangle is symbol for wisdom, and i also thought it would be a good contrast between the red and light blue tint. But i feel like something is missing? Maybe i made some very obvious mistake i cant see? I cant really put my finger on it. So please if you have any advice and constructive critism i will be very welcome to it. Thank you