I am not the biggest Giordano fan, but trading him will create a bigger hole on the blueline than we have down the middle right now.
Tanguay is playing pretty well as a centerman, except on faceoffs of course, but he has been playing with one of Iginla (51.6%) or Cervenka (57.7%) all season.
Stajan is holding down the fort as the #2 center. He has been good in both ends of the rink and is about 50% on faceoffs currently.
Jones is ideally the #4 center but he has been playing well, he has been generating energy and chances while actually winning some faceoffs (58.1%
)
Backlund is probably gone another month and will replace Horak/Street when he comes back. If the Flames feel the need to acquire a center I would prefer they go after a clear cut #3 center that can kill penalties and win faceoffs. Someone that will cost much less to acquire than O'Reilly.