PlanetSide 2 has pay to win mechanics meant to coerce players into paying for equipment to avoid the extremely long grind it takes to earn anything in game. A brand new player with a deep wallet can customize their gear to their prefered playstyle giving them an advantage over those that opt not to pay.
ESO's character system is based on skill lines; each class provides three. There are dozens of other skill lines, including all weapons and armor, which are open to all characters. Resource stats (Health, Stamina, Magicka) aren't tied to class either. This means any character can use any gear and be built to fill any role.
There are only six skill slots (five regular, one "ultimate") available at any one time. A character can swap between two equipped weapon sets, making at most 12 total skills available in combat. With well over 100 skills to choose from, finding two characters with exactly the same build is the exception, not the rule.
Though "flavors of the month" will arise in any competitive game, ESO's versatile characters and MOBA-like limitation on simultaneous skill availability greatly reward creative builds and counter-building.
Elder Scrolls games have always placed the world's unabashedly bizarre mythology in the forefront, and ESO is no exception. Between quest storylines, hundreds of in-game books, passing NPC dialog, and the landscape itself, ESO presents a world that feels bigger than the player, and can be incredibly immersive.
While the game can be played in third person (which may work better in PvP), there is an option to play in first person view which keeps in tradition of the view found in other Elder Scroll titles. This gives this MMO the feeling of playing Skyrim or Oblivion, which should appeal to those who are fans or familiar. It is also a unique way to play an MMO, which could appeal to those tired of traditional third person view MMOs.