I won't call it "central" but more like the music plays a part in Macross' plot, hence more of a plot device when traditionally music is just a background music. And as for love triangles, its a recurring theme. I think we're just arguing semantics here.
I won't agree with you if you say the next Macross series SHOULD NOT have singing and love triangles, if that's what you're saying, bzdup. I'll just say BLASPHEMY!!