Currently the solutions for saving player data in the Entity API are lackluster. The 1000 byte limit kills the usefulness of entity objects, and entity files requiring multiple API calls to write and read data is honestly painful. Saving player data used to be extremely simple and reliable and now it's more convoluted. Playfab needs to make the Entity API more user friendly if you want users to migrate over to it from legacy API.
We started using playfab recently and all the docs pointed towards using Entity Objects and Files. We got screwed over first by the limit of the entity objects, and then numerous issues with files getting stuck in upload state and entity profile version mismatch errors. We finally switched to PlayfabClientAPI and PlayerData and all our problems went away. However, it was frustrating for us that when retrieving the matchmaking player data via GetMatchResult api, it had the entitykey and not the playfabID as well. So we have to do ANOTHER API call to get the profile of the player in order to retrieve their playfabID (master_player_title_id).
Please, simplify this Entity API and make it more user friendly and introduce a more simple solution for playfab player data.