The protagonist is so silly and adorable.
Is the protagonist in sun/moon more expressive than in the previous gens?
Or are all these doujins just wishful thinking?
Honestly, she's so unexpressive that it's kind of bizarre. She has one single smiling expression that never ever changes, no matter how desperate or touching or joyful the situation, and it started to look almost creepy and empty the more I saw of it. It's been speculated that she's actually a ditto mimicking a human, and the theory is fairly convincing based on her creepy smiling face alone.
You can kind of piece together the cheery, energetic, life-loving character that's usually portrayed in doujins by looking at how other characters react to her, because everyone else responds to her like she's the doujin character, and nobody seems to notice that she's actually a creepy smiling doll monster, so... She's implied to be silly and adorable, but you kinda have to imagine it for yourself.