|An exile's hideout|
The game has evolved substantially in the past year or so and there's lots you should know. For starters, the amount of content in the game increased dramatically.
Let's start by reviewing the history of game content that I've cobbled together from lots of sources including the official Wiki's release history page, forum announcements, patch notes and Grinding Gear Games' video uploads among others:
0.2.0 - December 2008 (video)Alpha
0.8.5 - June 2011 Start of alpha release notes tracking (and video)Closed Beta
0.9.0/1 - August 2011 Start of closed beta (and video)Open Beta
0.9.11 - July 2012 Addition of end-game mapping system (and video)
0.10.0 - January 2013 Act three release (and video)Full Release
1.0.0 - October 2013 Introduction of the Scion class (release trailer)Sacrifice of the Vaal
1.1.0 - March 2014 Corrupted areas / end-game Atziri (gameplay teaser and trailer)Forsaken Masters
1.2.0 -August 2014 Masters / master crafting and player hideouts (release trailer)The Awakening
2.0.0 - July 2015 Act four release (release trailer)Ascendancy
2.2.0 - March 2016 Labyrinth and ascendancy classes (release trailer)I think it's fair to consider these versions as the "expansion releases" of PoE, as they're the versions that substantially added to the content in the game. Some of them were actually called expansions (like The Awakening) and some were not (like the start of closed beta) but all of them changed the way we play and what we hope to gain in doing so.
Over the past couple of years (2015-present) I've seen a pretty dramatic shift toward not just the end-game crowd, but even just the average players like myself running lots of characters, trying lots of different things. In part, this is because the Masters from 2014 and the crafting system overall makes leveling much easier the second, third and so on, times around.
But in part, I think that this is because the complexity and richness of the game has expanded so much that it's worth it now, more than ever, to go back and start with a new perspective.
For those who don't know why this is true, let me give you a quick overview on what a "build" is in this game. It's not what you might think of from other games (e.g. ARPGs like Diablo or even MMOs like WoW). To start, when naked, an exile has no skills. They can swing a sword and that's about it. So a build begins with gear and the socketed gems that go in that gear. Want to throw lots of fireballs? Put the fireball gem in your gear and link it to the greater multiple projectiles gem.
Then you have the gear itself. Unique items modify your character in subtle or profound ways, perhaps turning that fireball into cold damage or giving all of your attacks a gory visual effect.
On top of that, there is the mammoth skill tree! This thing is a monster that makes computer scientists giddy when first seeing it, but can actually be intimidating to many. The so-called "passive skill tree" doesn't give you new abilities, but lets you focus, refine and empower the ones you have. Every class has access to the whole tree, so the only advantage to one class over another used to be where you started in that skill tree... no more.
Now there are Ascendency classes, which modify your base class and give you dramatic new bonuses. These passive skill options are restricted on a class-by-class basis, so the witch can't take the templar's totem-enhancing ascendency bonuses.
This really enhances the replayability of Path of Exile, making every build fundamentally different from every other, in terms of gearing priorities, flavor and mechanics of skills (even the same skills!) and the plethora of advancement options.
Plus, some builds are better at certain end-game activities (like speed-clearing maps) but not at others (like completing the end-game Labyrinth), so it can be quite useful to have more than one fully advanced character.
Does this mean that you have to play lots of characters? Not at all, and many do not. I just think that that's where the community has been progressing for the past couple of years.