Thank you for all your hard work with the last-minute beta! This fic would never have worked without you, chiralove and our Noble Dragonish Capitan.
You're right, I've never read a bringing-back-Hedwig fic either. I wonder if this is because although she was given a distinctive character, she is still 'just' a bird, and in JKR's universe, another snowy owl is likely to be very similar. Hedwig is therefore replaceable. To a lesser degree, Weasleys are interchangeable (red hair, short tempered, very loyal, quite bright etc etc) and so there aren't that many bring-back-Fred fics. Colin Creevey is easily replaced by his younger brother. The people who are brought back are the ones who stand out as distinctive; Snape, Dumbledore, Sirius, Lupin, Tonks, Harry's parents, Regulus, Moody and if villains are required, Voldemort, Wormtail and Nagini.