If the bad harvests of the 1780s had never occurred. And maybe the third estate worked with Louis XVI to make a constitution, still strongly in the monarchy's favor, but a little closer to England's government.
What would happen next? No Napoleonic wars, the Spanish and Portuguese colonies in the Americas might have to wait for their independence. Some of the governments in Europe might be less Anti-Revolutionary, without the benefit of seeing a King killed.
How would the world be different without a French Revolution?