In a summer production of
Wizard I worked on (not my design), the
basket flew in on an upstage
lineset, and was only a custom
flat rigged with hemp rope. It flew in between a SL and SR series of low flats that had previously formed parts of the city of OZ (about 2-4 feet high at points). This happened behind a
drop very quickly. When it came time for the
basket rope to be accidentally let go, much screaming followed and many of the ozians rushed the balloon. The
Wizard then quickly ducked down and replaced himself with a cutout (actual photo mounted on black
foam core, but this could be done on
luaun or similar by a good painter). The
wizard crawled offstage, hidden behind the flats, delivering his lines as he went. The cutout then flew out with the balloon. Believe it or not, the
effect worked for children, and it caused a good laugh for the adult members of the audience - after all I think that's what the
Wizard of Oz is about. Another possibility would be to do a similar
bit where the
wizard falls down when the ballon is suddenly lifted and all you see is his costumed arm or him bent over (a cleverly placed mannequin flipped up or over the
basket) as it
flies out and he crawls away. If you didn't want to use the idea of him crawling behind a groundrow, you could also have him lose an article or two of his clothing so he blended in with the other Ozians and remained onstage leaving with them.