What about splitting up individual types of data into different keys/scopes/stores?
Inventory could have its own store, with each item having its own key (if necessary, if not, just keep all under one key - and perhaps limit the total number of items available in one’s inventory?)
Quests could have it’s own datastore. One key could be used for the quests a player is currently doing, and another could be used for the quests already completed (solely the IDs - and for current quests possibly the progress or whatever suits)
Player House data can have its own store, saving only the necessary information.
I don’t know how recommended it is to use separate stores, it may be frowned upon, I don’t know. Though, especially if you do need a lot of data, it may be a viable solution perhaps?