Only a very few airlines manage efficient boarding. One being Singapore Airlines calling up passengers by row so they can remain seated until being called up. No lines, no rush just pure perfection even when boarding some A380. The other is Ryanair with sort of rude rules to be respected and strict checkin procedures and deadlines but finally managing a perfect line of passengers to stand "at attention" (children, elderly and handicapped in front) next to the apron glas door before the arriving flight moves in.
I was once told chaos boarding is fastest.