i think they should not limit the contestants. let them sing whatever they want, taking into account their own strengths and the interests of the audience and judges. i have no problem if it's all in the same genre, as long as it sounds good to me. i would just want them to give it their best shot with whatever they have and not put artifical constraints on them. i'd like to see how good they get when they are at their peak, not how average they can be when they are singing stuff they are not comfortable with. no one's gonna pay them anyway to hear stuff they dont excel in, so why bother trying to get them to perform every which way. 😊