I realise that you recommend the use of Entity Objects over Player Data for storing player related data for a game. But i do not see why..
If i use Player Data, i can store simple k/v pairs or i can also store a JSON as a value. For objects, i can only store a JSON.
Second, if i want to update a single item/field in an object, i need to fetch and store the full JSON. But if i use, Player Data then i can store that field as a single K/V pair.
Finally, though not very important, one gets only 3 free objects but much more Player Data k/v pairs.