There are three variants of the Jazz mold: G1, G2 and Stepper. There is even a gold lucky draw/limited edition Diaclone variant. We will see a MP Jazz sooner or later
I hope they don't reuse Wheeljack mold for Sunstreaker. It deserves a new mold. There are Diaclone variants that TakaraTomy can reuse the mold: "red" and police cruiser. In fact, e-Hobby reused the G1 Sunstreaker mold to reissue the police crusier variant under the TF branding.