Molly Weasley is not the most loved character in HP fandom - some people think she's terrible. Just like other mothers in literature. I'm thinking, right now, of several of Jane Austen's mothers.
Molly Weasley was channeling them all. Lady Catherine (who would do anything for her daughter), both Mrs Dashwoods, Mrs Jennings, Lady Middleton, the older Mrs. Musgrove - all of these ladies, so often despised by reader and child. And leading them all - Mrs. Bennet. Yes, she's often silly and certainly short-sighted and no one can play favorites like her, but she loves all her daughters *that* fiercely. I can so see her wielding that wand.