There are many suggestions in the plot that are worth exploring, but for now, notice that when Matilda grows to become more powerful, her own mother has mixed feelings. She wants to feel like a proud parent, but when Matilda reads books, her mother starts to get a frustrated feeling, like maybe her daughter was becoming more powerful than she. Matilda is becoming more powerful by working through the complexities of life from Dickens' story-telling.
Mr. Watts is also called Pop Eye, which might be taken as a symbol. Remember that Matilda isn't with her father, so not only is Mr. Watts the only person that Matilda has by way of a male role model, he is literally the only white man still left in town, and he serves the community by sharing what he knows. But, he admits right away that he doesn't actually know much, but he will teach what he can.
Ironically, Pop Eye becomes a father in an intellectual way in Matilda's life. He teaches her the gist of problem solving, how to approach the human life (taught by making the kids read Dickens) and he teaches Matilda to think for herself, especially in the dangerous, perplexing place they live. They are on the cusp of serious violence, and they have already seen some of the rebellions beginning, but nevertheless, Matilda must measure he feelings for survival against her mother's petty desire to be powerful in the home. Matilda quickly learns how to be emotionally independent. She spends her life trying to understand Mr. Watts, in much the same way a heroine wants to understand her own father.
