Maybe some overall thoughts rather than answering questions?
I got mine yesterday so not had much time with it. But camera performance could be better IMO. It's also a little slow processing photos.
Portrait mode looks a bit on the poor side compared to competitors.
Battery life? Looks to be just ok for me but not even 24 hours useage yet.
I'd agree with most of what you've written above.
I'm coming from a Huawei mate 20 pro by the way...
The battery life on the Xperia 1 is ok but not great (certainly not compared to Huawei). Gets me through the day though and can usually get around 4 - 5 SoT...just. I suppose that's about right for 3300 maH battery and a 4k screen. It's only been 6 days though so things might improve....
Charging times are good but again not as quick as the Huawei.
Screen is nice, looks sharp but it is a shame that you can't change the look of the screen, vivid, warm, cool etc etc.
Feel of the phone is good. I don't notice the phone being too big or anything, feels natural and I like the big screen. Makes my mate 20 pro feel podgy when I use it.
Speakers sound decent.
Audio quality to my BT headphones (not Sony ones yet as still waiting for those) is very good but I'm not sure I notice it being much better than other phones, not that that is a bad thing.
I like the os, seems to be quick and responsive. Near stock experience. Needs a dark mode though.
I'm really hoping the cameras get an update of sorts. Low light it seems to struggle. Best bet in all conditions is to go onto manual mode and put HDR on. It doesn't seem to be an option in standard modes.
Wide angle lens tends to have the fish eye effect more so than the Huawei.
Still getting used to it all. I do like it but I think they could've done some things better, but hopefully a firmware update can help sort the cameras??