The quickest way to reach HLBC, which can be considered "the end goal" is simply spending thousands of real dollars at the oracle for nobility, and purchasing gold. Otherwise, you're stuck hitting EBs if your only goal is HLBC. Enjoy the game how you will.
I don't really know if this is a game to be beat, but when I joined a couple days ago I joined a clan and stuck with it.
Delphin you forgot about amassing atk bonus from allies and climbing the overall leaderboard, which are better measures of accomplishment than just HLBC.