Question about weapon, returning player

[MistakeNot]

Hey, I've recently returned to the game, just finished the ARR main scenario and currently questing in Heavensward at 64.

My weapon is still Artemis Bow Atma ilvl 100, and I have no idea whether I should go back and continue something, or if something better turns up later in Heavensward, and what I need going into Stormblood.

Hope you can help

(If you are in HW I assume you are level 54 rather than 64)
You will get plenty of gear as rewards from MSQ and some side quests, enough that you will not need to worry about gear until you hit level 60. At that point you should be able to spend a bunch of tomestones to get good i260 gear.
I think there are also NPC vendors now that sell basic i255 gear, which is enough to do all the level 60 duties and start Stormblood.