I am new here. I normally post over at
www.starshipmodeler.net under the name publiusr. That is a nice starship and mecha area.
I must say that I am blown away by the fan art you have featured here. Dorothy is my favorite of course, and to me Lia has the voice of a real angel. Cartoon network choose not to show episode 20. I wonder if this was because her character was badly treated there. I think I would have had things go a little differently, with Angel going to Dastun.
Here is something to think about. David Hanson at the University Of Texas at Dallas has been working on a (head) type robot with features more human like than creations such as Kismet.
There have been problems with human-like robots in the past creeping people out. But Dorothy has about the most innocent face you could imagine, and with a little work, Hanson's K Bot could have a replacement with much friendlier features. In a recent article in Popular Science, we are introduced to Mr. Hanson, who fashioned K-Bot from his assistant Kristen Nelson. Many social workers were excited by the lifelike job he did, which could aid the handicapped, since some have problems reading facial expressions.
I would like nothing more than to see such an innocent face as this immortalized for all time--
www.paradigm-city.com/fanart/dorothyc.jpg
Perhaps even as the real thing in the distant future. I am new to Cartoon Network, and the last I saw, her character had her mind removed.

I think it is time it was put back.
David Hanson's wonderful work can be seen below *
I must say, K-Bot looks more like Kristen Nelson's mother from the side, so a bust with fairer features might be what it takes.
The problem with making a lifelike robot is that--past the spartan Kismet-design, you run the risk of having something very like a walking corpse--like the mannikin's from that episode of Kolchack: The Night Stalker
I don't think you would have that with an actual R. Dorothy type design, especially with some voice sampling thrown in for good measure.
As for Roger--he's a louse.
David Hanson's page is here:*
http://iiae.utdallas.edu/projects
david.hanson@student.utdallas.edu
Pass the word--I'm outta here.
PUBLIUS