Originally Posted by
Revolutionary_Jack
That's the thing, an AU or Alternate Universe is fundamentally about plots and established dynamics not character-building outlines. It operates on a baseline set of assumptions that exist in the canon.
"What-If Gwen lived" works because we have some idea of who Gwen was, or what Gwen represented so AUs like "House of M: Spider-Man" and so on and so forth make sense.
"What if Uncle Ben lived" which has been done many times works because we have some idea of what Ben represents to Peter and so on.
Whereas nothing definite has been established of Peter's parents.
The entire story would have to devote way too much time to establish them as characters and sell what they can add to Peter's life.