It's a matter of opinion, but if you don't like many of D3's changes to its aesthetic or streamlined character skill trees, then Path of Exile could be your logical alternative choice. Instead of having mainstreamed skill trees PoE boasts a robust and very deep skill web that allows any character to do an almost infinite number of different builds for any class and the art style and persona of PoE simply feels like it went where I had initially expected D3 to go, but did not. This does not mean I don't like some of D3's new changes, I just feel like some of the changes are more indicative of other Blizzard titles and don't fit the mentality that Diablo should exude quite as well.
The skill web in Path of Exile is generalized to every character class and has literally hundreds of passive abilities that every class can reach. The only thing that differentiates one class from the next is where they start on this giant talent web. All of the skills on the web are passive abilities, but they add great depth to your character's build.
It's the Skill Gems that give your character their actual utility talents, they don't come from a tree or point allocation. Gems drop like any other piece of loot or are given as quest rewards. As long as you meet the gem's requirements and have an open-socket in your gear that matches the same color as the gem itself, then you can use that ability. So, my Templar was able to 'raise zombie' if I had an open blue socket, or he could do 'whirling blades' if my character met the dexterity requirements and equipped two one-handed swords.
The skill web in combination with the skill gems makes for an extremely flexible character creation system. It reminded me a bit of the Guild Wars of Diablo. Seriously, you can do anything you can think of with the points and skill gems allotted to create your character.
Check out this character, he's like a paladin thunder-striking, necromancer.
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