In America, Pullman and parlor cars were routinely placed at the rear of the train, with coaches at the head end. At many places where through cars were added or dropped, that arrangement was maintained by the manner in which cars were switched.
Another point I find interesting is that in the 1920's the Great Eastern Railway (and later the LNER) operated a very intensive suburban service between Liverpool Street Station and the Lea Valley. The trains had three classes, with the carriages painted in three different colors (I don't know what they were) so that passengers could quickly identify the class. The position of the carriages in the train was democratically allocated, since the trains were not turned at the termini.
Another point I find interesting is that in the 1920's the Great Eastern Railway (and later the LNER) operated a very intensive suburban service between Liverpool Street Station and the Lea Valley. The trains had three classes, with the carriages painted in three different colors (I don't know what they were) so that passengers could quickly identify the class. The position of the carriages in the train was democratically allocated, since the trains were not turned at the termini.