Do you think maybe Lily was great at potions because she likely studied or partnered with Severus in class, OR perhaps many of the notes made in the Half Blood Princes copy of Advanced Potion making actually notes Severus made from Lily's discoveries- she just died too young for anyone to realise that she was the potions savant?
@The Dark Marc no I think she’s actually the one who TAUGHT Snape all the Potions talents! That’s probably why he wrote down all the notes in his book. (Although I cannot confirm this for sure since this’s just my personal guesswork and no information like this is mentioned in the book/film series or on the HPW Fandom network.)
I don’t think we know enough about Lily in order to accurately assess wether she’s more intelligent than Hermione. But with that being said however, though she seems bright, she probably isn’t brighter than Hermione.