Currently Monika only interlocks her fingers or leans on one arm when not talking. I think it would add a little more life to her if she could also do the crossed arms and arms beneath the table poses with some various facial expressions.
I think the crossed-arms pose would definitely look natural for idle poses, I'm not sure about the arms-down one.
I don't know if it would be weird to add it in with the existing blinking/etc. framework but having her occasionally look left or right might also be fitting?
[closing until we look into it]