Have LUKE born on dagobah (padme survives).

The Tantive IV then goes to Alderaan, where a scene opens with Bail Organa says "We have always thought of adopting." (but no reference to a girl, this suggests he is planning to take LUKE).

Obi-wan looks concerned and approaches a sleeping padme (taken from from earlier) she mutters 'obi wan'.

We now see General Grevious' fighter on a landing pad, which obi-wan enters, on his lap is a baby. He then flies off into space .... alone....

This was all mocked up by someone else ages ago. I think its a good ESB style ending.