I could imagine for many carriers the shorter landing gear is a feature of the design; I believe some using this airframe choose to disembark passengers direct to the tarmac using the system's ladders, rather than involve a flight of stairs or an articulated gangway, lessening airport fees.
Edit: not to lessen any of the other points you made - this absolutely should have gone through approval as a new model.
Edit: not to lessen any of the other points you made - this absolutely should have gone through approval as a new model.