My advice for this would be; don’t add any more characters, you’re writing a Novelette (Under 20k words), you don’t need a bunch of POV characters. Focus on fleshing out the ones that are the most important to the current plot, otherwise you’ll just end up with a pool of underdeveloped and shallow characters. For Book 1, if you’re leaning on having the story centered more on Connin, I would focus on making him the predominant POV (he has the most chapters and/or is doing the most in the story), because ironically in “The Bastard” Marilla would be the predominant POV.
Focus on fleshing out Connin’s motivations, his wants, his needs and his goals.