They could add another 10 dungeons to end game and the OP will still not like the end game because he will say running dungeon #1 is faster so the other 9 are useless etc etc .

Unfortunately like most theme parks they are usually are over once you cap level except a few where developers poor millions into , the end game they have tacked on to this game is just to keep you playing a little longer .

What you probably want is some sort of Sandbox type game , EVE maybe ?