Tip: You can use Lunar Magic's Overworld Layer 3 Editing system to edit or create your own layer 3 images (castle bricks, fish, rocks) and apply unique effects per level via the Layer 3 Bypass in the main editor.
The space song everyone loves. This is kind of repetitive, especially in the second half, thus I suggest it for short levels in general. Theme-wise, obviously, it fits any level where Mario flies trough the level.
Personally think it's a tad too loud but everyone can easily edit the global volume to their liking. Despite it being repetitive, I was hoping you actually ported the entire song, a lot of parts are missing after the interlude and/or are shorten tremendously, and some of the chords afterwards sound off (if you used the MIDI floating out there I blame this on it since those chords aren't accurate). Because of this, the build up before the outtro is nearly gone (the volume rise is too fast). The vibrato seems a bit too fast but this is probably to compensate for the SNES's tempo being slightly faster than the original. I do love how you handled the echo and the pitch bend at the interlude. Good stuff!