Personally, I would suggest trying out GrapheneOS on a modern Pixel before going to iPhone. They remove 80% of the Google annoyances and have a very good security profile compared to anything rooted and most custom ROMs that don't bother with relocking the bootloader.

You will still fail to pass device verification, but that doesn't really matter to me. I don't use tap to pay (that's why NFC credit cards are for) nor play any mobile games that actually care.

I could not imagine using a stock Samsung ROM personally, but to be fair, it has been years since I tried. Maybe I'm still just too burned from the bloatware of the early Galaxy days.