Sandbox mmorpgs aren't the answer because developers don't offer an experience or adventure the payers have to create their own experience which leads to the majority of player base being lost and standing around looking at each other. Themepark mmorpgs main problem is they have only a few rides at end game centered around capping tomes, dungeons, raiding and pvp. There really aren't a lot of role playing and character progression in mmos theses days. Single player games have more role playing and character progression than mmorpgs which is sad.