UPRC, its a competitve game, there will be tournaments and stuff, so in order to stay balanced you will eventually (very quickly, actually) reach the top power level, and it will take a bit to get all the skills (but you dont need all of them anyways), and eventually you'll get all the items you need for the couple builds youll want to run, but there will be tournaments and stuff to compete in too and prizes to earn.
So, I guess, it really depends on what you're going for. Are you playing it to possibly win prizes? Do you plan on unlocking everything? Do you strive to get the highest rank...? If you answer yes to any of those, then its gonna have some staying power.