Dr Who Doctor 10 plushie WIP

A friend of a friend asked me if I could make a plushie doll of Dr Who Doctor 10 for her, as a commission. I wanted to make this doll for myself too, so I'm making it anyway as a test before the commission starts. I plan out my plushies on paper first like this.

I need your help guys: I'm not sure about what to do with his mouth! Do I keep the grin (Doctor 10 seems to grin an awful lot - I think it's cute, it really makes me smile!) or use a normal smile?

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