31/1 - Characters' max level is increased to 250!

Because instead of being something cool or shiny like CS stuff, its MOAR grinding. Nobody likes grinding, NOBODY.

Pretty much this. There are a number of ways to create a game that continues to hook people. Instead of revamping their dead pq system, increasing their boss spawn times, or improving boss rewards, Nexon went for the easiest (and worst, in terms of player-happiness) solution and simply boosted the level cap, and that's why I'm not wowed by their level-250 thing. It's lazy, and it's a little insulting since part of the content's success relies on the notion that the player-base is so addicted that they'll come running back to the game they thought they'd finished, solely to keep their rank intact.

There was a great video done about Power Creep somewhere on youtube. In it, the narrator refers to an online collectible card game that was bought out by a money hungry company that proceeded to make all the old cards worthless. The company thought their player base would be addicted enough to spend more money creating an entirely new set of cards from scratch. Essentially, they took every player's completed project (their deck of cards) and said "NOPE, you're not done yet!" Where people like you might have suggested embracing such a change, most players saw it as a great opportunity to quit the game altogether. And they did. Likewise, Nexon expects players who have "finished" the game to see this change as a good thing, even though every level 200 player I've met has expressed no wish to grind even more than he/she already has.

TLDR: there were ten thousand better ways to keep people hooked after hitting the level cap. Nexon chose a really poor/insulting method. If you want to embrace more grind, though, be my guest.