> Not sure if there is some way to iterate given online feedback.
There have been a some novels and novel-length works written a chapter at a time in public. The Martian by Andy Weir, for example is probably the most commercially successful. Many works by qntm (https://qntm.org/fiction) that are popular in this community have been written that way too.
Weir may have invented a new genre: STEMcore. His narrator-protagonists face a series of puzzles which they resolve with imaginative STEM skills and... well, that's most of it. I mean, he sets up a pretty good near-future world and gives the protagonist one big problem to resolve that helps drive tension (making it a quick read), but ultimately you're reading a short story that ate a physics textbook.
STEMcore (which, to be clear, is just a term I made up) mostly solves problems with STEM. Contrast with something like The Expanse which builds the setting from (some) realistic physics (plus a few enabling premisses) and mostly solves problems with politics and tactics.
I think Fifty Shades of Grey has had more commercial success than The Martian. It was originally published as an episodic piece of Twilight fan fiction (Master of the Universe)
There have been a some novels and novel-length works written a chapter at a time in public. The Martian by Andy Weir, for example is probably the most commercially successful. Many works by qntm (https://qntm.org/fiction) that are popular in this community have been written that way too.