It may take longer than a year. I wouldn't expect them to be done for another two years, maybe more.

There is plenty of flushed out content and well worth the price but indeed, I would expect at some point they will need people to reset worlds. So far they have been able to avoid it but you can't really count on that.

Also they expect to raise the price when done.

If you think it is the kind of game you just want to "beat" once and be done with it then I would wait. Personally I have lots of hours and lots of characters and worlds I have played through. I feel it is a game I can come back to at any time and just start a new character and get the full updated experience.