GZ! you reached level 110! Here is a list about what you can/should do in 7.2 after hitting max level.
1. Hit the AHEdit
Go to the auction house and get your gear in shape with some iLvL 780 greens and 805-835 blues. Later you'll see that 780 items drop from a lot of places, including raids and they are quite much useless for those who get them so they tend to be cheap/affordable. Check both armor and artifact relic categories. You can score some good deals, like Nighthold BoE epics with 870 iLvl for 2k-3k gold.
2. Get you AK to 25Edit
Artifact knowledge to 25 is virtually instant if you either can supply 500 order res per knowledge level or send an artifact knowledge token from your other high level character.
3. Get your artifact in shapeEdit
Do 1-2 world quests for AP tokens. Since at AK25 they give a gorillion AP you'll go over 20 traits with 1-2 token.
4. Do the Broken Shore intro scenarioEdit
Talk to Khadgar at Krasus' Landing to begin the scenario. While inside:
- stick with allied mobs: from what I saw once you attack something they start to do mad damage to those enemies
- don't run forward, unless you are a self-sustaining tank
5. Do the AK26 questEdit
Khadgar starts the quest from Deliverance Point after you finished the broken shore scenario. Quite painless with flying. Do the two flight-point exploration quests meanwhile.
6. Finish your class order hall campaignEdit
I advise finishing this after you get AK26 because it awards two AP tokens which give 1M-1M AP at AK26. While you are busy enjoying the ebin five timegated order hall follower missions, do world quests. Focus on invasions and broken shore WQs.
7. Get your gear in shapeEdit
Spend the nethershards you get from invasion/Broken Shore WQs at Deliverance Point for 850+ epic welfare gear (they all have the usual chance to warforge/titanforge). NOTE: trinkets and rings are Unique-Equipped so don't waste your shards on two tokens from these for the same spec as you cannot equip two dauntless trinkets/rings.
If you have a lot of shards you can buy Relinquished tokens from the ethereal there for 5k shards. They start from 880, can be warforged or titanforged and there is a chance that the token awards you a legendary item!
8. Start raiding, heroics and mythicEdit
If you pass iLvl 825 you can start doing LFR and heroic dungeons. However with Dauntless items you can go above 840 easily and start doing mythic0 dungeons too.