Liana was more of a "localized" issue than dropped content. You did mentioned Elisa which was the "Anna and the Snow Beauty" event but it's techically dropped due to the announcement of the game getting closed. There's also the "Shadow of the Devil King" event. As for the rest, it were the Gold Rush/Save The Witch events that weren't really worth doing as they were replaced with other content. Though to be fair the other content has better availability since Save The Witch became a tutorial event and the rest appeared in the Trading Post.
Fair enough.
Hopefully Aigis gets the same treatment, but the question is does Osawari Island still get events due to that? Most of Aigis's good content until Makai were about the events and new events.