World content/PvP
So from what I've read, there is a big emphasis on world content and PvP. I don't have an issue with this to some extent. I would say it starts to get problematic if that's the only place for any relevant and challenging content(ignoring the griefing that will occur).
If the only place to get good items/gear is through these world bosses, where does it leave people that are not interested in doing what is essentially PVP for gear? How complicated will these world bosses even be? Is the only difficulty aspect of it having to fight other people in order to loot it? I don't mind pvp being a good place to get good rewards, but if it's forced content to be relevant in the game, then it becomes an issue.
Replay value of instanced Dungeons and the value of instanced raids
So, the main point of instanced content in the game is for story purposes, correct? Will there be any point in revisiting dungeons after you have been through them once? What about raids?
One of the best features Blizzard added in World of Warcraft was the Mythic+ system. For those unfamiliar, you get a key that you can put in at the start of the dungeon. The key level starts at +2 if you have never done a dungeon before and goes up indefinitely. The only way to increase the level of your key is to successfully complete the dungeon under the allocated time. So if you have 36 minutes to complete that dungeon, completing it by that time, your key level will go up by +1, or +2/+3 if you do it earlier.
There is a popular third party site/addon that tracks all of your keys that you have completed and gives you a score. It's a great way to be competitive and gives players the drive to keep pushing as high as they can. For anyone else, the increased rewards and difficulty add replay value to dungeons you initially did while leveling.
Without the Mythic+ system, you would have no reason to set foot in dungeons EVER again after you finished playing through the story or finished leveling.
The raids are also competitive and there is a community run world first race for the top guilds. There are
4 difficulties for raids: Looking for raid(LFR), Normal, Heroic, and Mythic. Looking for Raid is the difficulty meant for those
that only want to see the story of the game or have no care for doing more difficult raid content. Then you have normal and heroic, which is the entry point for everyone.
Mythic is where the biggest challenge comes in and not many people are able to clear it. If you manage to kill the last boss at mythic level, you are rewarded with a mount and an achievement. You also have access to the best gear in the game(which includes high rated PVP/Mythic+). I've noticed a lot of emphasis on exclusive content, but again it seems to primarily involve open world content. World content whose difficulty will probably be
dealing with griefing.
Open world content that will probably eventually get
monopolized by the top guild(s) in the server.
I guess I'll start saving up gold in order to reserve a spot in their raids.
Everyone else.
I wouldn't call myself a casual. I can push relatively high keys in WoW and I am in a mythic guild capable of achieving cutting edge(achievement for killing the last raid boss in mythic difficulty before the tier ends). So I take part in content that about 1% of people that play the game do.
One concern I have is will I be able to get any top tier loot or any meaningful loot unless I'm lucky enough to tag a world boss that will probably be controlled by a few people?
You can have difficult content in instanced dungeons/raids that only a few people are able to clear, but in those cases, everyone has a chance to go in there, try, and have a chance at going as high as you can. I am honestly disappointed about the afterthought PVE content seems to be. My friends also feel that way, people that are also competitive and love difficult PVE content.
What about casuals?
A lot of people like to think the casual player base can be neglected. They like to ignore the fact that casual people make up the larger part of the player base in a game, and if you neglect them, well.....
your game isn't gonna live that long. I would say World of Warcraft does a good job with the different difficulty options for Raids and also the lower key level range for dungeons.
So if you're not that interested in getting the best loot in the game, or clearing the hardest content in the game, you still have something fun to do.
Conclusion
I'm terrible at writing conclusions. Anyways, I think for the long term health of the game, it's important to have great instanced content and not put all your eggs in one basket. Have difficult content options for PVE, PVP, World content, etc and let people choose what they want to focus on, and if they are good enough to be top players, to get great loot for it.
Not everyone can achieve a high rating in Arenas or battlegrounds. Not everyone can kill a mythic boss or push high keys. And in the case of Ashes I guess not everyone can kill a world boss.
All of those content types deserve equal treatment, in the sense that they should all provide meaningful content and rewards for the people capable of achieving the best ranks in that respective content.