Savage being midcore content is the greatest lie being told on these forums, and people truly believe that. Its incredible.
Just because you can clear a tier after months does not make it "midcore". Most people can clear any game if they keep banging their head against it and practice playing. That is the player improving/learning, not the game being easy/midcore/casual.
As for whether Unreal and Extreme are midcore - that is definitely debatable. To me, they are not, because they require a certain amount of organization and are not simply "drop in" content.
All these examples though, Unreal, Extreme, and Savage, have a trouble with replayability and longevity.
What this game is lacking, imho, is repeatable, unorganized group battle content. Where you jump in, you do your thing without needing any pre asigned spots, and then its GG and leave. In that vein, I have yet to do more than one lockout of Chaotic, but it seems like at least in P1 you don't exactly need to organize yourself with other party members. A lot of personal responsibility there however, and its very punishing if you make a mistake. We'll see how that develops in the future.