I don't know if that belongs here exactly : my feeling is that 'crowding' the map by two (increase nb of opponents) increases more the difficulty than raising a difficulty level. I'm early in my experimentation but I find I get more pressure with 8 AI civ level than 6 AI HK difficulty.
Which brings me to another point. My game starts to feel very 'civ6' like where I get pressured at start and if I survive the initial war for territory, which I mostly win (although I miss a bit of experience against HK huns, I need to play them once to understand the extend of their dependency on outposts) , then I can strive and play peacefully to the end rushing eras not caring about star levels and the AI stops being a competitor.
In HK level I'm usually 6thn in fame at that point in a 10 players game but not for very long as I start to climb exponentially .
Granted it's more ''intuitive' than 'definitive opinion' as I don't have all the time in the world to play everything.... plus I'm starting to become a one-trick poney playing invariably Egypt for high prod start , Achameneid because I want moooar cities , Khmer because more prod , I stabilize with Ming because I overexpanded/overbuilt my cities plus I need to catch-up on some leftovers civics because my INF when for my expansion (if not war) , and I finish with science, rushing era INF buying all the wonders because I'm so advanced I have free time to pick-em-up and they all take one turn to build as an 'half-empire wide effort' and I end-up winning a science victory... every single game.
Reading forums , I feel people have a very different experience where they have to care about farming high level stars, my best friend and my wife play science/gold early combo with babylon as do some here but I'm better than them when we play together. I have read about gamers ending throuh pollution ... did not even know that was possible...
Not sure what makes my games so different from what I read around...
I'm not even fast , I win alway early 200ish turn (three last games turn 201 funnily enough)....headscratch