Rusty effort
What I think you did was a noble attempt at the simplicity of the original 8-bit wündertune, but it fell flat on its face for a fair few reasons; firstly, there was never more than one instrument including drums playing at once, the 8-bit may have made it famous, but this is the 21st century where anything is possible. Next, there were too many instruments all jostling about to get attention for the main theme. Be creative, invent your own counter-melody to quietly pique your listener's attention, or harmonise to achieve an "epic" quality. Then there was the issue of the electric guitar which had far too much reverb on it, you could hardly pick out a tune towards the end of the song. Coupled with the fact the track volume was too low at its genesis, then too high to accommodate the reverb, it just created a "sound mess".
With only a few tweaks here and there you could make a credible version of a classic tune, and truly make it your own. I hope my words inspire you to, at the very least, try again.