There are really tons of stuff to do.
PvP, achievement prizes, sightseeing, crafting for housing, making gils, raiding, tomestones, gearing and playing more than 1 main jobs, Gold Saucer MGP farm and prize hunting, crafting/gathering/fishing logs, lvl Chocobo to rank 20, lvl many or all jobs to 70, Hunting, Extreme Primal farming for mounts, Artifact Weapons etc.
I'm subbed and actively playing almost every day since 2.0 launched and I'm still doing things I've never done before.
There is a lot of content and by the time you do 1 of these a new patch is out bringing more things.