I have this same slipcase set and I m quite happy with it. If you buy directly from Chaosium you also get the pdfs so I have used both quite a lot. @EthanSental the quickstart rules and adventure are very easy to follow and is a fun scenario to run.
You can try and use Ana B. Meyer version. Is a very modern take on it but she has a version for the different eras etc. just google her name and Greyhawk and it will show you her page.
Well depends. If they do new Adventure Paths and adventure modules they can certainly do a players handbook as well even though it might not be the main selling point. Slowly they can shift the people to buy their manual instead of pathfinder etc. Is going to be a nice experiment to see. Now...
I think the Desert of Desolation mummy name was Amun-Re (at least his body was a mummy, I think in the sarcophagus by the staff of ruling) you encounter his spirit as well. At least that was my understanding.