How many Point of View characters are appropriate in a novel?

How many Point of View characters are appropriate in a novel?

      I am currently struggling with an important question while working on my newest novel. How many Point of View (POV) characters are appropriate in the sequel to Hour of Trial? The sequel (sorry no name yet) has more points of view than Hour of Trial. It needs to have more POV characters because while Hour of trial occurred in a couple main spots, however, in its sequel, the story expands. Non-POV characters were introduced in Hour of Trial and now their importance is growing but should the reader get to hear the story from their point of view? Are they that important?  If you have read the Hour of Trial or if you have an opinion, please tell me whom you want to hear from.

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