I like the earlier William Gibson script, one of the early ones where Ripley wouldn't be in it and Hicks and Bishop would spend the movie kicking alien arse. Model Soldier, the one you refer to is a later draft I think. You can read the Gibson script online though. It was cool but very cold warish, and the Berlin wall fell just after he finished writing it.
The final script was a weird conglomeration fo ideas from earlier drafts, i agree the definitive edition is better (despite soem really bad sound) but I still don;t love it. Also, the Alien never looked good in Alien 3 for me, too CGI - though i think that is due to the compositing of it onto the frames. It looks so much better int he shots where they use a model, like the one where it comes close to Ripley's face. I think in general the models in Alien and Aliens look fab compared to CGI though.