I haven´t read any of these space theories. My interest for astronomy comes from two sources: one is a children´s book from Brazilian author Monteiro Lobato called Viagem ao Céu(A trip to heaven) from 1932, which takes his character´s on a trip through the Astronomical heaven then known.
The second source of inspiration is astrology, because of it´s relation to the planets of the solar system.
A third source is this thread. I´ll have a look at Moffat. My own guess about all these speculations is that the human urge to dominate space has increased in the last decades. It reminds me very much of the theories the Europeans had about the ocean and other continent at the beginning of the period of the Great Navigations,