And this new parallel universe should be an experiment. In which you can introduce Sally Acorn and the Freedom Fighters (and Snively) from Satam and Archie comics (since there was evidence that all the characters of the Universe created by DIC Entertainment still belong to SEGA), Sonic's family from Underground (mother Aleena, sister Sonia, and brother Manic), Agent Stone and Longclaw from the movies, Cosmo from X, Sticks from Boom and many others. It can be Ultimate Marvel (from the 2000s) and IDW Teenage Mutant Ninja Turtles for Sonic. And what the new Lara Croft reboot is now trying to be. Which will pay a lot of attention to the backstory of the characters, their development and the interconnection of the Universe.
Sonic's backstory in the Unified Universe can be put like this: first of all, I would tied his origin with Shadow and ARK, as Shiro Maekawa (writer of Sonic Adventure 2, Heroes and 06) originally wanted. Before ARK incident, Gerald Robotnik experimented with blood of