SEGA failed in the console business with the Saturn and Dreamcast, then went 3rd party but have really been mediocre at best when really they should be one of the big 3rd party companies.
They own some really great ip.
Sonic, who at this point needs to get rid of all his dickhead freinds at make some great 2d & 3d games, if mario can do it why not sonic.
Golden Axe really this could be made into either a hack slash or RPG.
Streets of rage its amazing there's no new game after all these years.
Crazy Taxi was an ok game a few tweaks change of city each time like London, Tokyo etc, have story mode an arcade mode.
There's plenty more ip they could use, but what do u feel about what they should do?