first thing i would do is cut some note envelopes into that melody and bassline, it's kinda just one volume the whole time and it's kinda boring. note envelopes will also help you put accents on the most important rhythmic parts of the melody so that the timing of the melody doesn't get lost (louder drums would help that too though)
also there's a thing that you can do with a lot of different chips called pulsewidth modulation (or just PWM) and it sounds really cool and you should grab a synth that will let you do it. magical 8bit plugin would be good cause it locks you into the 3 basic pulse sounds that most old chips used, although if you used something like synth1 or ts404 if you're using FL you can get that really smooth PWM sound like the commodore SID chip could make and which a million demoscene/cracktro people sampled later on.
anyway keep it up, listen to lots of modern chip music to see what the meta is like at the moment, and hopefully we'll see more from you later!