What you call "the Golden Age tradition" of stringing stories together into novels was not so much a tradition as a consequence of the fact that almost no genre SF novels were published between 1926 and 1946.
I don't know if there is any one secret to successful writing, but one important step is to move beyond imitation and discover what you can write that no one else can - that is, find out who you are and write that in an appropriate narrative and style.