How's this for a new format?
http://who-transcripts.atspace.com/sample.htm Or something very similar. The borders could be smaller. From your comments, it seemed as though the general consensus was that a mix of formats from series 1+2 and series 3, incorporated with a more traditional script format, would be easiest on the eyes.
I'll need to think of an easier way of coding it, though...!
So, what do you think?