As someone who might soon switch to an S23 after being an iPhone user since the 3G, this is a great thread to have. I've just grown impatient and annoyed with iOS's lack of software quality.
The other forums have (unsurprisingly) strong biases towards their phone choice and it doesn't really help when making a decision. So, thank you for creating this thread and for everyone's contributions!
Best of luck and that is why I gave up on iPhone's too.
My suggestions are:
Sync your contacts with a Google account prior to switching.
Deregister iMessage on your existing phone in advance. Note: you can still iMessage and FaceTime with others from an associated e-mail account logged in on a Mac or iPad.
RCS messaging generally works well with one-on-one iPhone user chats and groups of people including them too. The only downsides are that videos sent from iPhone users are of lesser quality and sometimes photos I send to them are not delivered (they are if I use the Gallery app to select and share so it may be a Google Photos odditiy/bug).
Learn the basic in's and out's of Android navigation which are different for sure and take time to gain proficiency.
I find Samsung's additions to "pure Android" are beneficial other than many of their duplicate apps alongside Google's offerings. The Samsung specific ones I use are:
Expert Raw camera (with direct Adobe Lightroom integration)
Gallery (similar editing and magic eraser functionality and sends photos more reliably)
Secure Folder (isolate/encrypt financial +similar apps and data separate from everything else stored on the device).
Smart Switch (to make local backups of my phone to an external SD card connected via the USB-C port).
I would steer clear of Beeper and Sunbird iMessage utilities due to major
privacy concerns!
Be careful what additional apps you install. I use
Goggle Advanced Protection program to scrutinize Play Store apps to a somewhat higher level of security and privacy.
One thing I never liked were the default launchers other than on OnePlus devices. For consistency when switching between different manufacturer devices, I decided to use
Nova launcher. There are numerous other launchers to choose from if you also find the default offering to be less than ideal.