Whatever you've enjoyed doing from 0-80, you can really kind of keep on doing it.
If PvE is your preference, there's probably a bunch of zones you haven't seen (world completion), and there's the Living Story to always check out when they add another episode. Sounds like you wrapped up your personal story, but haven't hit dungeons yet. They're very satisfying, and since you've played for a while you have a grasp on why the so-called chaos that others describe is essential to the experience. I recommend GAF groups if at all possible, or you're likely to run into people who want to skip cinematics, cheese bosses and do all sorts of things that sap the fun out in the name of efficiency.
On the other hand, World vs. World is always dynamic, though your experience varies based on who's commanding, how many people you have, etc. I haven't played much more than an hour or so total since the end of the Tournament, but that was my fault for burning myself out. Now that the Living Story has ended, I'll probably swing back in there on reset night. It's usually a great time, whether you're running with the pack or havoc squading around the map and maybe picking off a few larger objectives.
I'm also finding (thanks mostly to Moondrop) that PVP isn't nearly as awful as I was expecting. Especially if you're going in as a group with a strategy. I'm someone who swore off arena-style PVP after World of Warcraft's was so off-putting, but all of my complaints (The trinity is not conducive to PvP and gear should never be a determining factor) are absent here. I'm genuinely surprised how much I've been enjoying it lately (though in small doses).
On top of all of that, you can collect skins (there's more lurking around low level areas on Karma vendors than you might think), work on achievements (completing the Jumping Puzzles category is the most fun and satisfying, in my opinion.) or the ultimate game changer; roll an alt. Since the professions are so different, it changes the game pretty significantly.
Finally, you can just stop playing.
Yes, really. Play a different game. Try a different hobby. Go outside, even.
The beauty of Guild Wars 2's endgame is that there really isn't one in the traditional sense. There isn't some special, specific thing that you do over and over again forever until the end of time. The game stops when you want and waits for you to come back.
"Guild Wars 2 has an end game" in the same way Mario, Zelda, Uncharted, Final Fantasy, Halflife, Halo, Grand Theft Auto, etc. have no endgame. They're just games, full stop. It just happens that Guild Wars 2 "adds more game" through the living story / feature updates so there's a reason to play it again from time to time.