[...] Yori could take a break from it, since she has already won Kino's affection and the right to hold her hand, the most intimate action a yuri couple can share.
Everything else aside, I don't think Yori taking a break would be a good solution here, seeing how she herself started out feeling uncomfortable performing in front of others. Wouldn't want to take all she's gained away from her now. Nothing wrong with having two vocalists, though.