Whether you’re talking about self-publishing a novel or pursuing a traditional publishing deal, in both cases the only valid answer is that it depends on the manuscript itself. I say that because if a novel is marketable, it’s marketable, regardless of what literary condition it was in at the very beginning. After the average publisher is comfortable that a manuscript is marketable then its time to look at whether or not its cost effective to pair one or more editors with that writer to whip the manuscript into shape. That’s where the talent of the writer and quality of the writing comes into play. Think of it like that show “Dancing with the Stars”. They pair up celebrities and athletes with a dancing coach, train them up a bit, and then let them compete on the dance floor. Really, anyone that can stand and move without physical assistance could do it but the show’s producers don’t have that kind of time to invest in the train up. Some ability already has the be there.

All that said, if I were in your shoes I’d focus on refining the manuscript. That’s the key. Make sure the story is tight with some interest plot-conflict arcs. Without a completed manuscript, everything else is a waste of time.

Best of luck on your quest!