I think what fans want the most is some kinda insight to what the hell happened in Destiny’s ending. How Kira ended up in ZAFT and how he’s doing after that. Is Lacus really become the chairwoman? If yes, how could that happened? What becomes of Cagalli-Athrun-Meyrin. What become of Gladys' son now that his mother decided to die with her boyfriend and left him alone
, and so on. Many fans will be pissed if the (assumed) new series/OVA doesn’t addressed the above matters at all and just go with new characters and new conflict. It'd be nice if they also show how Sven & Serene was doing after being rescued.