Most international carriers with high security standards (read El Al, Air India, etc..) already have some version of most of these points in place.

Two clarifications to your points though.

Not all the hijackers were seated in First or Business Class. Only one or two of each group were up front and the rest were in coach.

All foreign visitors to the US (as opposed to permanent residents) are already required to retain their I-94 card in their possesion. The I-94 is stamped with date of entry as well as the date that the visitor is legally allowed to remain in the US till.