The song, and I guess the chart too, has the Shades of Grey syndrome, where it's not interesting or intricate enough to make a great chart. The only real way around that is to switch up the chart from common conventions, like the kick drum being on 1 or the bass being on only one key. You've definitely got some good ideas though, like at 0:38 where the low notes of the melody are on higher keys. You may want to simulate the ride cymbal too for added interest. But really the biggest drawback is the song itself. I'd suggest keep doing what you're doing, but pick a more rhythmically demanding song.
__________________  eh | 
my first IIDX simfile! 
