KIND OF STRANGE...!
A few months after KOTCS came out, I had a dream about seeing the Last Crusade in a theater on a warm summer evening. It was pretty much everything like the movie, except at the very very end, it showed Indy going to the moon in outer space.
I left the theater thinking I really like the new take on the Last Crusade.
With that said, your idea is not half bad.
But Indy V is not being made. (would loved to be proved wrong here)