Thank you very much for this useful thread Varti
Two factor authentication - this might be obvious to others but it wasn't to me - during the initial setup I couldn't get past the authentication page showing the picture of a USB key (which I sometimes use with Google for 2FA).
Then I realised that I had to scroll down to see the other authentication options like SMS, etc. But I don't recall seeing a scrollbar or anything indicating that there was anything further down the page. At first I thought there was no choice.
Also, if you generate backup codes
https://support.google.com/accounts/answer/1187538 from the Google accounts security page first before you try to sign in using the Gemini, then you can use one of those codes if you have issues with the sign in e.g. with texts not being received.
Finally I found that you have to reboot not just to disable the keyboard vibration, but also I tried to disable then reenable the screen rotation, but it wouldn't rotate again until I had rebooted twice.