I would absolutely not trade Kira for Ro.
But if I could add Ro without losing Kira I'd absolutely do that.
Ro/Kira might have had some interesting chemistry. The hardcore Bajoran versus the anti-Bajoran. The Prophet devotee versus the Bajoran who doesn't give a crap about the Prophets. The resistance fighter versus the woman who hid out in a Federation prison. Kira would have hated Ro, and it would have been awesome to see that.
I also tend to think that after what happened with Cardassian and the Dominion, nobody pursued the Maquis survivors that hard afterward.