Thank you Alex. I just wanted to highlight this part of your comment because I'd never even heard of Alle meine Entchen, and I just now looked it up and it's not familiar to me at all. I always find it fascinating what listeners bring with them to the music when they listen.Especially the throw-ins and the allusions like the Tango Argentino or the "Alle meine Entchen" (all my little ducklings)
As for motivic consistency, the work as a whole is materially bound together by a set of key motifs and figures. My view of musical atmosphere is perhaps different from yours. For me atmosphere is a fundamental emanation of the Idea, the first principle after which the work is created, that contains everything, contradictions and all. I don't know if that explanation makes any sense; it's something I've been meaning to write about at length for some time now, but I'm not able to get stuck into that kind of project right now.