I wouldn't mind seeing Soejima working on SMT at all. But only if the rest of the Holy Persona Trifecta goes along with him; have Atlus call it a one-time experiment that they hope will draw Persona fans into the rest of SMT.
Drawing Persona fans into mainline SMT games would follow their current strategy of involving Persona characters in a game whose structure would be akin to mainline SMT which would be... Persona?
I don't get the point.