Gearing, in dungeons at max level you'll get tomestones you can trade in for gear or use the dungeons themselves to help get gear. Once you hit max level what you do is ultimately up to you.

You can run extreme primals for mounts/rewards join a raiding static get into crafting and/or gathering or level some other jobs. Best to talk with some FC mates and see what they would recommend or if they have a spot for you in some future content runs.