How ar you going to do Shadow and Knuckles ages what with Shadow being 50somutt in a 16 year old body and Knuckles being 4017 in a 17 year old body?
P.S. The Characters are now a year older since Sonic Chronicals for example Sonic is 16 and Tails is 9 and as Shadow dosn't age his body is 16 (Knuckles was in some sort of suspended animation simmalar to Shadow Exept Shadow wouldnn't age anyway). P.P.S. If you have any questions about Shade come to my Watchamcallit (site?) (it's a little bare I'm a new member and there for haven't gotten around to useing it yet) and post them in my comments also check out
[link] the Sonic wiki page on Shade(other pages of intrest to you for info on Shade would be IX the Echidna, the Nocturnus, the twilight cage, and the Sonic chronicls: the dark brotherhood page).