Part II: Could Louis XVI and Marie Antoinette have avoided the guillotine? The scenario you propose, where the Levée en Masse (mass conscription) occurred ten years earlier and Louis XVI retained French soldiers instead of foreign mercenaries, presents an interesting counterfactual historical scenario.
“Had the storm of the Levée en Masse not erupted for another decade, perhaps we could have built a stronger dyke against its fury. A French army, bound by loyalty and fueled by national pride, might have stood firm against the revolutionary tide.” – Louis XVI