I don't understand how anyone thinks MJ's absence is a problem for the movies. MJ not being in ASM is completely orthogonal to how well or poorly Gwen's story was handled. MJ being present wouldn't fix any perceived issues people would have had with Peter and Gwen's relationship. In fact, the primary reason why Gwen's death was so controversial in the films was because people liked Gwen so much. How does MJ being in these movies fix any of these problems?
And again, I like MJ but this just feels like putting her on a pedestal she does not belong on.