Game Freak and TPC have big things planned for Lillie in the future. You'll be seeing a lot more of her in both the games and anime.
What those things are exactly, I won't spoil, but they're big.
>>32912872
Those are some big plans
>>32912882
For you
>>32912872
No.
She's just going to be another "landmark" character. Other than that, there's nothing special about her other than her merch selling like crazy and her departure likely fueling that given the trauma it left on players.
A character leaving forever or dying can have that effect on a fandom.