So? I only considered it an issue for mechanics reasons, since you needed your Persona for stuff like Bursts. But if they found a way around that for Sho there's no reason they can't do it for Dojima.
If we're talking about unrealistic match-ups they threw out that idea awhile ago. Even with a more combat focused Persona, Rise shouldn't be anywhere near the same skill level as the other characters. That's just one of those things you have to suspend your disbelief in a fighting game.
Rise makes complete sense because her Persona changes from a support one to a combat one in the story, potentially with the help of Elizabeth. There is no suspension of disbelief required there, especially since Persona evolution has been a recurring element throughout the series, alongside the evolution of one's psyche.
Every single choice in P4AU's roster is based around narrative. This is why the Persona 3 main character is not a playable character, and why Dojima would be an idiotic inclusion (which Atlus themselves have stated).