Actually, multiple audio mixes wouldn't be a big deal to do on a DVD. The trick is whether or not they have good sources of the original three mixes
(mono, stereo, six-track Dolby). I'd really like to see them include them all, although I'd settle for the original 6-track Dolby mix. I don't like the remixing and additional junk that Ben Burtt has added in over the years.
I'm hoping they release the "Star Wars" crawl version, too. That's the "original", and anything else is going to just bring George even more grief.
(They could easily add the "Episode IV" crawl as an alternate angle though - that's what I did on my DVD transfer, so it's just a matter of whether they want to or not. There's no technical challenge to it.)