It's been about 6 years since I played the game. I have the physical copy of the game, but for some reason Square thinks that if you haven't played the game after a year, they completely get rid of your account. Making it impossible to play the game again unless you buy it again. So, is it worth it? Were there any changes since 2004?

I think they changed the class system so members of a group could decrease their level to the level of a lowest member of the group enabling everyone to gain exp. The ones who lowered their level would also get a lower level counterpart of their equipment automatically. I quit the game before they introduced this feature so I have no idea how it worked in practice but I bet you know how much it changes the game, you actually can play it with the people you want to pay with no matter how high their real level is. This was 2 or 3 years ago and I only played it for 2 months so I didn't really know much about the game at the time, let alone how it is now.