What ends up happening then, is I either don't post any long form stories (novel length) or I post a bunch of scenes or vignettes that may or may not be related to each other. When they are, I lump them together a la "City/Seasons" or "Charlie's Bar." I only have a couple that are true short stories in terms of length, and that is mainly because that is how they ended up but they are really just longer scenes (Bad Porn being an exception to both as it is a movie script).
There's a big difference between short story writers, who tend to write, like you do, in vignettes, often exploring techniques, and novels/serials, for which the story/plot is paramount. Thus it's hard to transition from short explorations to one where the focus is 'story above all else'. If a story segment doesn't drive the story forward, it gets cut, no matter how interesting or 'beautiful' it might be.
Most long story writers begin with a specific end point, though they're not often sure how they'll get there (the full details of the story). The problem on SOL, is we often get 'serial' writers, who start writing on a chapter by chapter basis, and they never have a clear endpoint in mind, and they never move their stories to that end. Sooner or later, they realize they have no exit strategy, and eventually they grow exhausted and end up posting less and less frequently, rather than wrapping the story up--which just frustrates everyone, author and readers both.
Novel writers need to be like newspaper writers. When writing daily newsfeeds, you're telling a very specific story, and you want to keep it concise and focused on the story. There's no room for personal observation, personal opinions or conjecture.
Novels are similar, if a subplot is interesting, but never goes anywhere, you cut it. If an interesting character doesn't go anywhere, you cut him. More than anything else, novels are concerned with conflicts, rather than a specific plot, so the effort is dedicated to developing those conflicts, resolving them a piece at a time until you reach a final conclusion. Any of those individual minor conflicts can be cut, but you always keep your eye on that final resolution, and arrange (plan) things so you're moving towards it at all times.
Until you learn to think of stories in those terms, you'll continue collecting vignettes, hoping to find someplace to use them.