Thank you for the good thoughts! I also appreciate the analysis you've done and the constructive critics.
My idea was to keep a little bit of the harshness of 1 bit Z80 sound. I've added a lot of "overdrive" effects but it was on purpose. I wanted to stay on the original sound as much as possible that's why something gets lost on parts. I tried hard to balance the output mixer so I can get some acceptable proportions while staying in this self-imposed envelope.
Also I haven't actually finished it, there are some parts I simply gave up working on and abruptly finished it.
I'll give a shot at the indicated tunes as well. I hope I can get my hands on some original sound to work on.
: later edit :
I had another go at recreating the roughness of the original version here but with a twist:
http://www.digitaverna.ro/img/trantor_3.mp3