Once you move beyond Rowbotham you find a lot of disagreement, unfortunately, on the height of the heavens and their size. Terra Firma talks a bit about this. One thing the majority, myself excluded, believe is that they are substantially smaller and closer than in other conventional worldviews - to account for the contrary assumption to that of Eratosthenes. There is no doubt his work was important and his influence strong, and I agree that it would be a useful text, it just happens to be one that I haven't examined in detail. His work is on my list of zetetic authors' work to get intimately familiar with.
In general, the wide majority of literature on the flat earth is biblical based, stemming from the 1900-ish Christian Science movement. Rowbotham being the best at separating his zeteticism from his religious beliefs (in ENaG, most of the biblical material is at the end, in a comparatively short section) seems to have the most supporters here, despite several differing views. I have to assume its due to the almost unilaterally secular view of the society (born both out presumably of need and philosophical soundness.)
On a side note, I feel like many of these writers should have taken better account to Job, at least in a less literal sense as they often talk of Job due its imagery concerning the description of God's creations. Their use of their brand of reason mimics the issue in Job's mindset - God made this, so to question his order or reasoning based off of human point of view is silly. In short, the ethics and morality of God are not those of men, nor is his design sense - a repeated meme in several of the monomyth. Given Job is one of the oft most quoted books for planism, one would have hoped this angle of its message was not ignored.
As you move away from the 1900s and towards 2000 the movement and writings shift more and more away from religious context and into a more "conspiracy" based fringe|pseudo science view.
One thing I'd love to see here, and it is a thing I have been slowly injecting into our threads, is a movement away from a strictly Rowbotham / Shenton view or at least quoting so in part folks can see why, in this example, the community went with 3000 miles over 700. We have our own set of views that developed out of many of these texts and also our community and they are in serious need of review and organization. The fractured nature of the communities views (Rowbotham strict, Religious (outside of forum use mostly), Rewritten History, Relativistic, Aetheric|Bendylight|Law of Perspect, and Infinite|Finite Earth to name a few) is one of our strengths, as we wish to examine an unorthodox view from as many angles as can be possible, yet it also breads confusion.