I'm not bashing on anything, just hear me out.
I have a feeling that Battle of Azeroth wasn't actually planned to be the expansion after Legion, but they decided to squeeze it in mid-development instead of the other expansion that was intended to follow (now known as 9.0), as a by-product.
Edit to clarify: I don't have anything to say about the Lore/Story, I think the direction it's taking is fine. It's the gameplay and features of this expansion that I base my theory upon. No matter what gameplay or features an expansion provides the Lore could always be and end up the same, regardless of features.
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Why?
For me, Battle of Azeroth is Legion 2.0; it comes with improvements and some new content, but very minor features. Minor features that appears to be a huge questionmark for the developers (as for now), it seems like they barely have any idea yet how the features will work out, as if the features are still in early development. The entire expansion only builds upon Legion (not really a bad thing), but barely add anything new to the table, drastically reduces the amount of development time required.
The 4 "major new features" of Battle of Azeroth are all minor.
- The Heart of Azeroth is built upon Legions Artifact progression-system.
- The Islands Exploration feature is mostly different templates of small islands/areas with limited variables of "randomly generated, dynamic, content", built with or based of the already existing Scenario feature.
- Warfronts. Stromgarde, the Warfront, was a very early work in progress by the look of it, of an expansion supposed to be developed for over a year. Shouldn't it be more finished or why wouldn't they otherwise show us a better work in progress? It seems like Warfronts are the latest feature they decided to add and still early in development. They base most of the content from Warcraft 3, why? To reduce development time?
- Allied Races - re-used assets, it doesn't even appear they'll have their own starting zone. A good feature overall, but it's so minor.
Edit: I forgot to mention the social features, however, my opinion still stands. This is a minor feature, most likely built upon Battle.Net API, not developed by the WoW team.
Where's the new
MAJOR FEATURE?
I've also seen a lot of reused assets in the footage we've recieved, more than ever before. It's not a bad thing, just mentioning it (reducing development time, again).
I think they want 9.0 (the expansion after Battle of Azeroth) to be "huge" and "the next big thing" and want to give it more development time. So instead of releasing it next, they squeezed in Battle for Azeroth.
This is why I also believe why they announce "Classic WoW". They know Battle of Azeroth is a risk to stand alone and in order to try to stabilize the player base and income the game generates they have to do something drastic. Battle of Azeroth is "half an expansion" and Classic WoW is part of the other half that would make out a full expansion. It's only technical issues to deliver Classic, the content already exist to some extent. I wouldn't be surprised if 8.2 is the last patch for this expansion and we already get a new expansion announcement next BlizzCon (2018).
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Also, I've noticed this before in their expansions, some of this is my opinion of course, but Battle of Azeroth takes this to a whole new level:
Vanilla - ?
TBC - I don't believe there was much cut content for TBC.
WotLK -
Mostly great expansion with a lot of content and story.
Cataclysm - Lackluster expansion, a lot of cut content (yes, I know the world-revamp took a huge amount of man power).
MoP -
Mostly great expansion with a lot of content and story.
WoD - Lackluster expansion, a lot of cut content.
Legion -
Mostly great expansion with a lot of content and story.
Battle for Azeroth - ... Do I have to say anything?
9.0 -
Mostly great expansion with a lot of content and story???
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TL;DR
- Battle for Azeroth wasn't intended to be the next expansion, is a by-product of 9.0.
- A lot of reused assets, reducing development time.
- New major features are minor and some are based of current/old content, reducing development time.
- Classic WoW introduced to keep players subscribed or get players to re-subscribe if Battle of Azeroth will fail (huge content-droughts). Seperate team(?), content is already there, only technical issues.
- All this in order to get more development time for 9.0 (expansion after Battle for Azeroth).