I have reached level 24, and really don't have much to do but tend my garden and home. It would be nice to have optional daily and weekly quests after you reach a certain level. Just so you don't get too bored.
Quests are meaningless to me, and I just don't feel that this is a quest directed game. I have my own goals, and quests simply are distractions that delay those. In fact, the majority of quests that are in this game are just introductory skill tutorials.
Besides, at level 24, I'm not convinced you have nothing to do. You probably still don't have all 11 icons, and there are skills you are learning that you could work to speed up.
I would much rather get more sandbox tools and more player-driven goals than have the magic rock tell me to make ten of an item and drop it on a vendor.