Fun combat and the core maps are free to play. If you enjoy those first couple hundred hours you can then buy the expansions and the living world maps and thus unlock the entire rest of the world.
Would recommend playing with friends, but it's also pretty easy to find friends in-game to play with in any of the major cities or starter zones.
Story can be a bit lacking, but it's a non-issue since it's mostly optional and the game shines brightly in the combat and map design (where most of the game takes place). (If you do decide to play the story though, don't just skip through the dialogue. You make decisions that affect the next part of the story quite often, and you'll be confused and lost if you didn't read/listen)
Players are helpful and if you're confused are usually more than happy to chat and help.