Thank you, it's been a real labour of love!
People are raising a good point RE Touch ID. It is possible to add a fingerprint sensor. But that fingerprint sensor will never be able to do the things that Touch ID is most useful for: i.e. use Apple Pay. It would be incredibly confusing to have a fingerprint sensor that was usable for some things and not for others. Therefore the better experience today is to not include a fingerprint sensor at all, imo.