Ultimately it really depends on whatever you are willing to do
I could list off a lot of aspects in the game you could participate in, and that many still do (with the exception of deep dungeons, maybe, but I haven't done any of those myself in awhile.)
but a lot of people view the content as dead and thus not worth the time
So it's really hard to recommend anything

Eureka, Bozja, Relics
There's plenty to do in past expansions if you've already done everything you want to for this one
Could even help FC mates get through some of this content or introduce them to it
I always enjoy bringing new people to Eureka myself, it's a lot of fun

and for anyone curious, be sure to look into potions of harmony
They buff your EXP while in the zone to make leveling go a slight bit faster

If you're purely worried about gearing then yeah, it does seem like you have to wait
Though I'm pretty sure you can buy the augmenting items for sacks of nuts, can't you? Or whatever the current hunt currency is
I haven't checked myself, but I could've sworn that was a thing