If you are able to modify the games data files. You can modify the hero templates to remove the "<RequiredTechnology>no_heroes</RequiredTechnology>" line. This will of course break multiplayer compatibility (unless they also make exactly the same changes).
Moved from an internal WFG forum because I thought it was time to open it to the community, and it didn't seem like there were anybody's secrets in the thread. Just today and yesterday, we have had offers over the forums and the contact form to record sounds in Greek and in Punic/Hebrew.