Honestly, I liked the 8th Doctor version of Shada so well I can't really imagine the 4th Doctor in the story. Still, I'd watch it if they made it.
It'd be cool if they got the surviving actors together to do it. It's not the greatest story but it would be nice to see in an "entirety" and as close to the original as intended... I'd splurge for that alone!
Well, we're talking about the BBCi webcast/semi animated version. Released 6 months before Big Finish took the audio from the production and stuck it on a CD. If it was a Big Finish production I wouldn't have listened, but since it was a "webcast" based off an actual Doctor Who script, it was pretty good. I like the 8th Doctor, and if I counted anything but the movie and his regeneration as canon then Shada would be it. I might even call it "honorary canon" because I liked it so much. It shows what the BBC can do and how they do it so much better then BF, although it helps to have a solid script at its core. Its certainly the closest thing to canon a Big Finish person has ever worked on (since I know the director and the person who wrote the prologue did some normal Big Finish work as well).
You got your facts wrong. It is a Big FInish production. Just like Real Time, another BBCi webcast production was. The audio release was made first, and the webcast came after. It was overseen by Garry Russell who was the head honcho of BF back then. It was his idea to put the Eighth Doctor in it. https://en.wikipedia.org/wiki/Shada_(Doctor_Who)#Big_Finish_version_.282003.29 Honestly, its the only Eighth Doctor story that I personally discount (that, and the Auton story with Lucie Miller). Its so embedded to the Fourth Doctor to me that it doesn't make sense to me view in any other way. That being said, I kinda wish they'd do animated versions of some of McGann's audios, just to give him more visual range. Maybe his Mary Shelley trio of adventures?
BBCi release: May 2003 Big Finish Release: December 2003 http://tardis.wikia.com/wiki/Shada_(webcast) I personally take TARDIS wiki over wikipedia for Doctor who related things, plus Big Finish's website lists the Shada Big Finish release date as December 2003. The webcast was released weekly May to June 2003. So, BBCi came first. A BBC production that worked with BF for the audio bits but got reeleased by the BBC first so it makes it theirs. As for the story, for me it has absolutely no connection with the 4th Doctor except for 15 seconds of footage from The Five Doctors, plus I'll admit to probably liking McGann a bit better then Tom Baker (not that I don't like Tom baker, he's a very good Doctor but since I have no nostalgic connection to him I generally rank him around the middle when it comes to ranking the Doctors). So, since it was "animated" by the BBC that puts it in at least the same ballpart as canon, unlike stuff Big Finish does by itself. That doesn't mean it is canon, nothing not on TV is canon for Doctor Who, but if I was going to accept any non televised thing as canon it would be the 8th Doctor's version of Shada. As for other animation, it wouldn't make sense to spend even a penny to animate a Big Finish story. Unless McGann magically gets a TV special (which won't happen at this point), he's remain a Doctor with only two canon appearances unfortunately. He deserved a lot better, obviously.