I like the GitS manga, but there's something that could be said for how Oshii took the basic premise of the GitS manga and injected into it mood and spiritual ambiance. Of course, the manga and the film adaptation are two incredibly different beasts, but I always felt the film was much more cerebral and sophisticated, and the manga, while not any less so, suffered from a lot of what kills anime for me. It's hard to verbalize, but I find that a lot of anime and manga (even more prevalent today than 20 years ago) is too anime-ish, if you get my meaning. GitS Sac is good, but the "filler" episodes and secondary story arcs are often convoluted and honestly, I ++++ing hate those annoying, obnoxious Tachikomas (once again it touches upon the cutesy "anime-ness" I was speaking of earlier).
The original GitS is a masterpiece of anime art and pop culture. It's too bad it's follow up, Innocence, sucked.
The RAH Motoko is great, but it's not my favorite version of the character.