Resurrection Stone folks

[R. Penar]

No: HPFGUIDX 175868

You all are so much smarter that I am; I am wondering what your take 
is on this:  Why is it that *only* James, Lily, Remus and Sirius come 
out of the resurrection stone for Harry?  Why not Dumbledore, who has 
consumed more of Harry's thoughts in the last year than any of the 
others - in fact, Lupin has just died and Harry really hasn't had time 
to process and think on that at all?  Why not Cedric, Tonks, Fred, 
Moody, or heck, even Dobby or Hedwig?  And, related, it seems that 
Lily and James are as they were the night that they died; however 
Remus and Sirius are described as looking "less tattered" 
and "younger".  Why?  Did they revert to how they looked on October 
31, 1982?  If so, why?