My husband and I came a few months ago back after a similar long break and it took at least 1 month to "arrive" back in the game and like 2-3 to be really back. And we still discover things to do better/faster/more efficient than we do before lol.
But yea, Do Rhapsodies! All of them (you only need help for the last one probably) to unlock all those Key items. Those will get you more exp/cp, QoL adjustments like reenter times for content, more Trust NPC's buy all the shiny stuff from a moogle (Like coffer keys, ninja tools, food, RR ... and stuff).
https://www.bg-wiki.com/bg/Curio_Vendor_Moogle
(Re)learn how to travel around the world. There are not only home points everywhere, you also can use survival guide which you often find at start of dungeon-zones, Voidwatch warp and Unity warp.
https://www.bg-wiki.com/bg/Category:Transportation
Search and accept all those records of eminence Quest for Missions you have completed. The final reward will be Capacity point bonus. Missions will be all together 90% Bonus. Re-do all Rieves for RoE Missions.
Get some basic gear for jobs you liked before and see if you still like them. Don't go all out on jobs where you'll feel like you wasted your time. (mnk for example).
Best is to find some people to help you with Ambuscade or Escha-Zitah (once you unlocked it) and don't waste too much time doing things like Skirmish.
Get Trust and look for campaigns where you can buy more Trusts. Apururu is a cool Unity Trust, depending on your server (On Cerberus she is always 1st in Ranking), ArkAngel elvan is also nice for a tank, Koru-moru is also cool and you get him from Records of Eminence Starter Quests, same goes for Joachim. Cornelia is also good, she will not attack, but also never takes dmg and gives a cool Haste-Aura (and other stuff). This is like a good basic supportteam when you get Haste II from Koru-Moru and debuffs, some buffs from Joachim and he is allways fast with -na-spells (But can also replace him for another DD). Apururu is a whm who also runs out of range and like never out of mp. Most DD's aren't that great and Trust scale with your item level, so try to have 119 Item level to also have strong trust while soloing/lowman.