Options - you can make a berserker an archer, a templar a caster, a ranger a melee character. You can do just about anything you want with any of the classes. You do have the option to reroll a characters skill points, but it can get expensive so it's worth doing your research before you start throwing points into the tree.
Skill Tree - There's SO much you can do with the skill tree. While the meta slaves will tell you there's realistically only a few paths that make sense, this game is such that you don't HAVE to go with the meta to do the content and have fun. I was initially overwhelmed with the skill tree, because I didn't realize that the entire thing housed all classes.
Trading - My favorite part about Diablo 2 LoD wasn't getting to the end game and killing Ubers. It was the economy. However even that got to a point where you couldn't do anything with your PoE buy items you'd obtained except say you had them. The currency in this game is actually crafting material.
Fresh content - In the last year, this game has had a major overhaul of the acts, adding 6 new ones to the game (some layouts/chars recycled, but new acts nonetheless) added a bunch of new maps, and brand new atlas progression system, another big bad to the story line. There are constantly new unique items added that can completely change the way a skill or entire build is typically played.
I feel I've only briefly summarized the greatness of this game. Hope you enjoy your stay. Say one more thing, at U4GM, you can gather more PoE Orbs cheap.
