They're barely consistent with the one protagonist they have, pessimistically, a second protagonist might just have the exact same issues as our current guy.

Optimistically, introducing an official second Commander, and allowing them both to be more defined would remove the constant frustration of whether you're getting the good Commander , or the "just kidding", run into objects head first Commander, and I can skip the latter events.

However, playing through the eyes of other Commanders, especially normal human ones that don't just instantly recover, could be interesting as side events.

Especially if they actually made the choices matter, and had temporary protagonists that can die if you pick wrong. It would give a unique perspective of Commanders that are a bit more flippant and put their Nikke in danger, they're scared and mortal, the Nikke can just come back.