Well, the first thing you gotta know about what I think is that I really don't think Kid Icarus needs a second rep at all. With Zelda then, we don't know whether Zelda would have outprioritzed Ganondorf in Super Smash Bros. since they were both added at the same time. Arguably, Zelda was a higher priority, since she was given a unique moveset all to her own, but I still think Zelda has a different role than Palutena.
Zelda's much more active out on the field to help Link; in early games, following Link around when possible, guiding Link as Sheik, and in later games, using the light arrows in combat. Palutena talks and gives advice, and helps from afar. She's definitely the second most important character, but I think there are other characters in Kid Icarus who are more active in battle than Palutena. I'd say that Zelda has a much more active role in combat than Palutena in the first place, but then with Kid Icarus, I'd say that several characters have a much more active role in combat than Palutena.
It doesn't change Palutena's status as an important character, but it makes me personally much more interested in fighting as a character who is more active in combat, because those character exist in the Kid Icarus universe and Palutena is generally not among them.