Quark, interesting bit of speculation.
You're onto something when you analyze the survivors like that but don't forget Crocodilia in this analysis, who don't benefit from feathers or elaborate song, or extreme diversification. It was the mysteries of their physiology and their environmental adaptability, et al, that enabled them.
Also, remember that both of these surviving orders comprise branches of the basic trunk in the Archosaurian tree. Those that are extinct weren't meant for earth's more advanced stages of development, and they will never return as the dominant forms - perhaps in zoos.
Just look at them - everything typical of DINOSAURS made them targets for extinction. They are NOT representative of the Archosaurs, not the main thrust of the Archo line - Crocs and Aves are, and their success proves it (man's challenge is to remain until he can see what comes after the next global killer).
Dinos were an aberration during a very strange part of earth's past, and are a blind spot now, in the minds of too many "scientists".