Interesting...
I don't know the original song, which is a good thing. Means I'm focusing more on your actual work than what its "supposed" to sound like. ;-)
Well for starters, this is a good foundation. Like you have a cool melody line and a nifty little sounding synth playing it. Also you have a solid base for your percussion, which should make it easy to expand on. Here is where I would go from here...
First off I would add percussion. I would get some unique percussion packs online somewhere, be it freeware or something that you bought, it doesn't matter. You seem to need some better percussion samples so you can expand your sound a bit. Either that or create your own percussion samples like my one buddy does. Granted that takes more work, but you get the exact sound you want from them every time.
Once you get some new percussion samples, or create your own you can start creating new rhythms with them. What you have is pretty straight forward and bland. I would work on adding some sort of glitch effects to the percussion if it were me, that would give it some life for sure.
Moving on I would add some layers to the melody line here and there. During some sections I would have it layered heavily and in others I would drop a lot of the layers out so that main synth can just shine through on its own. Adding some filter effects would probably make the kiddies here on Newgrounds swoon, it always does really. I personally don't like them a whole lot anymore because so many people overuse them, but when applied sparingly and in the right places they can create great tonal changes to your song.
Also I would add some sort of harmony lines. A great way to do this would be to add a piano to the mix. Pianos go with nearly anything really, so adding one to a mix is super duper simple. You could create some rolling chords above the melody line with some thick hall reverb, or even have them in that middle range right below the synths frequency sweet spot but still above that "bass" frequency range.
And speaking of the bass frequency range, add a synth bass to this. It would be super easy to do and would fatten up the tone immensely. Really, there are two things a song can almost always use, a piano and a bass of some sort. This has neither, so add both and you shall see immediate improvements. ;-)
Lastly, I would lengthen this a bit in order to give it some more variety. Add some more sections that maybe have some call and response phrases in them. That would make it sort of easy to write and would help to fill up some space. It would also create some unique variety with the song that is lacking.
Hmmmm...I think that should be enough to keep you busy for a while. Best of luck bud. I'll reserve my true judgment for when this song is finished. Therefore you get a middle of the road score for now.
3/5 and 5/10 overall.
-Gravey-