That’s pretty much where I place Peter at, in age. 27 or 28 years old. Miles is 17 right? A nice ten year gap between the two Spiders. Since Ben was “dead” for a while, I tend to imagine that he is at least physical one or two years younger than Peter physically.
But yeah, I place Peter, Harry, Betty, Flash, etc, all in that age bracket. 27-28. Harry having children, really puts some age on him and Norman, at least in stories. I don’t know why but I always tend to think of a Norman in his late 50s.