Fury of the Dragons:
Originally there were ideas for two expansions and it wasn't certain which we would do next near the end of Legion. The Dragon Isles and what we got now with the Shadowlands. The covenant system could have went to either expansion with one being based off the dragonflights. It made sense to go with Shadowlands first with the plot of Sylvanas in the end.
The character who introduces us to this expansion will be Wrathion. He will play a role similar to Khadgar/Magni/Bolvar. The Dragon Isles are split into five zones which each being based off a flight. The Black dragonflight zone is in the center of the isles and will be a max level zone similar to Suramar. The story is more adventure centric due to feedback as far as early Legion for a more down-to-earth feel. The initial expansion is based off exploration with many sub-plots hinting at other expansions and some leading to the main story of the expansion itself. There are flashback quests involved as well with Malygos, Neltharion and even the Titans.
There will be the typical features you can expect with new dungeons and raids. A new talent row being added with some of the good covenant abilities we have now being included and the bad ones left behind as well as some brand new abilities. The other major feature is Adventures which are 10 man instanced PvE content. They are designed a cross between dungeons and raids aimed at the desire the community has given for something that feels like a raid but still a tight-knit group.
One of the major features as most can guess is the old world revamp. This will only include the two original continents but will include zones that were untouched last time (blood elf & draenei starting zones). This has been a long work in progress as far back as BfA with Warsong Gulch and Arathi Basin examples of what you can expect in terms of reusing art in old zones while being faithful. New class/combinations will be unlocked similar to the Cataclysm revamp.
Dragonsworn is the new class that is a hybrid of a new class and a new race. Mail armor wearer with a tanking/healing/caster dps spec. Tanking is based off the black flight. Healing are the reds and caster off the bronze. Blue/Green were considered but they didn't want to tread on existing classes too much however there are planned cosmetic glyphs for those who prefer them. They wanted to do something different with this class and so every race can become a Dragonsworn however like Worgen when they enter combat they will have their own dragonsworn form. This is customizable in the character creation screen when making the class and can be adjusted in the barbershop.
There will be a new borrowed power system. They still feel it has its purpose in order to not create too much bloat. It comes in the form of a new Dragon Soul. This artifact will not take up any slot and instead be apart of the UI where you can customize it. There is no artifact power grind coming with it. It will work like a mix between artifacts and essences with passive bonuses and a choice of one of five abilities themed after dragons. These are unlocked via major story quests during leveling and during the campaign at max-level.
Where from?