I agree, but Nr2 depends on how the speakers are made to perform. My speakers should be close to a well damped wall.
Nr6; according to my speaker maker you should measure the distance between the tweeters and take that distance x 1,18.
Take the result and measure that from the tweetewr plane.
If you have 3 meters between the tweeters you should sit 3,54 meters from the tweeters (mesured from the middle between the speakers).
Then you should toe in the speakers towards the listening position.
I dont know if i can explain this in english well enogh for people to understand

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In Sweden we had a speaker maker named Stig Carlsson, he made speakers from the fifties to the nineties and all of them should stand on the floor directly gainst the wall with no dampening (his latest models had dampening built into the speakers).
It worked really well.
https://www.carlssonplanet.com/hogtalare/carlssonhogtalarnas-historia/By the way i dont understand the word under Nr8; judiciously, newer heard it before