Is changing POV between protagonist and antagonist a bad plan?
Question: My original story is completely from the POV of the protagonist. I feel that I can make the story more "fleshy" if I switch between protagonist and antagonist POV, however I am unsure if this is frowned upon by publishers and readers.
Honestly, it depends on your story. You have to weigh up the advantages and disadvantages.
Adding the antagonist's POV can increase the reader's understanding and empathy for that character. It can add depth to the character, which can be a good thing, since no one likes cardboard villains. Readers can experience a certain voyeuristic pleasure from seeing into the mind of psychopath (or just a morally corrupt person).
Another use for additional POV characters is to create dramatic irony. They give the reader a chance to learn things the main character does not, which changes or nuances the reader's understanding of certain events.
Of course, the more POV characters you have, the weaker the connection the reader has with the main character. The more POV characters, the more the reader shifts to an objective rather than subjective view of the story. Since the subjective view, based on an intimate connection between reader and main character is very appealing to readers, you have to consider the trade-off. Your thematic message may be affected by your reader's perspective on the story. (For instance, do you want your reader to identify with your main character or be in a position to judge his/her actions?)
You will see all manner of variations in published and successful books. What really matters is...
1. Do you understand and effectively connect with your ideal reader?
2. Does the style of narration fit the story you want to tell.