I know nothing about this topic but will be watching it with interest. One little thought I had though is:
Is there any undiscoverd archeological evidence that would be really, really nice to find?
For an extreme example, there was some excitement over the James Ossirary (spelling?) which turned out to be a hoax. Wouldn't an ossiary with validated inscription something like "Mary, mother of Jesus of Nazerath who rose on the third day" and dated to say AD 50 or so be a cool find. Giving at least a scrap of evidence that there was an historical Jesus.
Some evidence of the exodus in the desert might be pretty cool too even thought the thread discussing that seems to make it clear that it is not likly to be found.
Of the supposed "90%" that is missing, what would we most like to find?