Welcome to end game! So, youre going to want to spend a little time getting your gear sorted out. Depending on the type of content you want to run, you may or may not need the very best of the best, but you still want a decent set for your main class. You'll upgrade this more or less every other patch. If you want to get right into extreme savage and ultimate difficulty instances, this is priority number 1 with a bullet. If thats something you dont care about, then you can just do a piece here and there while you focus on other objectives(and if you fall in between adjust accordingly). Grinding out 70 levels in three weeks on your first toon means you almost certainly skipped a ton of optional content. So now you certainly have time to go back and check out some of what you missed. Optional dungeons(a few in the "leveling" range, many at level 50 and 60, 2 currently at 70), optional trials, 8 man raids, 24 man alliance raids - theres plenty of combat instances to try out. You can start befriending beast tribes and gaining their trust. You can pick up crafting and gathering and try making some things. There are other classes you can try. Some people lose a lot of time on the gold saucer games(triad racing and minion). Others dedicate themselves to collections(mounts, minions, music). There are a few sidequest chains that are incredibly well done(Hildy being a popular favorite) which you probably missed. Have you met(and potentially been enslaved by) everyones favorite mi'qitten?
And of course, theres the TRUE end game if you think youre ready. Ill put this one under a spoiler tag, just incase your mind isnt prepared.
The TRUE end game is glamour. Making the prettiest, most badass, and best put together outfits to glamour over your own potentially ugly and not well matched gear. It is truly a war that never ends.
And i know im leaving some out, so clearly there are a lot of things you can check out! Part of being "caught up" in level and story is that you now get to set the style of game you want to play without feeling like youre being left behind.