Dan could be referring to the abrupt change to minor at 0:48, or the fact that there are 'two' influences. Usually, you'd only want one influence on a track so that it doesn't try to be every song at once, you know? You would find it out of place if a piano ballad went into a heavy metal section (not saying it isn't possible, but highly unlikely), so in terms of the NES and its limited capabilities, having two styles is enough to make the two sections 'feel' different enough.
I can't speak for what he thinks isn't enough compositional coherency, but I think it's coherent enough: you've got an A, A*, and B section before the thing loops again. Short and to the point! My only qualms with this is that the DCPM samples are very loud in comparison to the rest of the channels; I can barely tell there's a triangle (bass), and usually it's the triangle that's overpowering everything else with its lack of volume control! In addition, the B section at 0:48 does feel slightly out of place. The minor vibe is nice, but might be better suited for another track itself, just to keep the track in a certain vibe, rather than take it all over the place. If you really wanted to keep that section, I would suggest extending the track, having more of a build-up to that section, and then a wind-down from it, so as not to abrupt jump from major to minor (granted, that works in some cases, but now is one I don't think that it applies).
Other than those points, very nice work dude! I could easily see this in a campy sort of platformer that isn't trying to impress but just about having some fun.