I'm one that hasnt been playing much.. part burn out, part new baby... but for what its worth...
Like Usinea, I felt THF became a mq2 fest.. and playing with other people just turns into two bot armies..
When i was playing, i thought it would be more enjoyable if there was a simple way for any two players to play together on challenging content. "Helping" another player typically results in one bot army way overpowered for the encounter and not being challenging or "fun" for either player.
What if any player could take any one of their characters, even MysticKitty? for example, and scale them DOWN (not up) to play along with a lower tier/level other player character.. i dont know how that would even be possible, but something like a parameter/slide/item to equip that would lower your stats/skills/equipment down by some variable amount...
It may "work" to have complete sets of equipment of lower tiers to swap out, but bank space doesnt really permit that, it would be a pain to do, and still wouldnt address scale of AA's.
2 cents from a very part time and not current player.
Edit for additional point: I, having taken a break, cant just jump back in to play with my friend (shoutout joffy) because he has out-progressed me. I could borrow one of his characters and play as a singularly unsubstantial part of his bot army, with no healing (bots).. or we could choose two of his characters and try some duoing... and try to find some other player to group up with etc... or what if he could choose one of his chars and scale it back down to T5 from T9 and we could play together. Otherwise its me grinding up to him, or him grinding up to me with a new char.
Once someone has put the time into one or more characters, why not let them scale down?
And forgive me if their is character scaling already in some way.. but im only aware of content scaling.