Dark Forces was never a comic book. It was a series of three short novels with a series of full color pictures, which was published by Dark Horse, which is why it is often believed to be a comic book by people who actually had a chance to look at it.
I know Shadows of the Empire is only a audio book and not a full cast audio drama, but it is particularly well read, and very enjoyable to listen to. For years I have had an idea for a project, to take the audio books and set pictures to them from various SOTE sources, and master them together as a DVD. Maybe with a few extra features.
I purchased the audio books and the comics in order to do this, but there is also a set of Shadows of the Empire trading cards that I would like to include. I wish I could find high quality scans of the entire run. It would be really hard to hunt down a complete set of them, and probably very pricey too.
Two other good sources for art would be the book "The Secrets of Shadows of the Empire" as well as the cut scenes to the N64 video game (which are semi animated still scenes. The PC version has actual animated scenes.)
I still think this would be a really cool way to experience Shadows of the Empire, but I do not see myself getting time to do it anytime soon, and I would still want to get my hands on those trading cards before attempting it.
If anybody else wants to tackle this, I think it would be awesome.
As for other casted SW radio dramas, there is a short one called "Rebel Mission to Ord Mantell". It is written by the same guy who did the SW radio dramas, Brian Daley. He also wrote the Han Solo books. This story takes place between SW and TESB, and is suppose to be the mission Han is referring to when he mentions "the bounty hunter we ran into back on Ord Mantell" at the beginning of Empire Strikes Back.
This one was not all that well written or preformed. It is pretty juvenile, and obviously aimed at a younger audience. It originally came on a 7'' record, and was published in 1983, not sure if it was ever republished on any other media.
And as for the possibility of having fans reading scripts, don't expect very good quality, I have seen too many of these kinds of efforts (fan made radio dramas) come out unbearable due to bad voice acting.