In opera, arias are written for voice types that also relate to the role, so there is a definite classification of voice type/matched to song. A spinto tenor, for example, has a quality that can be bright like a lyric tenor, but also have a dramatic weight to it.

What I don't like about the song Memory is that there are a lot of low notes in it that don't ring out, and I'd like to hear her voice with a song that would use the strongest part of her range, really show what it can do.