The French had a larger army and more tanks than the Germans but the Nazis had technological innovation, audacious generals able to think and command freely and would have been on the offensive. The original Nazi plan would have incorporated the Schliffen Plan which would have sacrificed millions of soldiers on both sides to the horrors of trench warfare but 1940 was not 1914 and with the inventive use of tanks in the battlefield there is a good chance the Nazis would have broken through at any point in the line and driven all the way to Paris.
No. This is a silly view of the evolution of Plan Yellow. The Generals were timid souls who felt any offensive against France was doomed to fail. The original plan was not that of the Nazis but that of the generals. They, naturally, in keeping with their Dolchstosslegende tradition of "history" refused to admit any of this. Too, it ignores that repeating the Schlieffen Plan would put German tanks, badly underarmored, and the German Luftwaffe, right smack in the teeth of the Allied defense with superior firepower and mobility and thus it would have been a disaster for the Germans.
Germany's generals were a bunch of petty, treacherous, murderous backstabbing scum and filth who disgraced a tradition already seedy enough from the WWI army's penchant for shooting civilians at the drop of a hat if one soldier heard a farmer shooting a small game.
The Single biggest reason for the Nazis total victory was Manstein's relentlessness in driving the Panzers through pass their line of support, if Hitler had listened to his more cautious generals there was a good chance the Allies could have been able to regroup and stage a counter attack as at the Marne and led to static warfare for a few years with this time much of the devastation in Belgium not France.
Strategically, yes. The reality is that this was a tenuous victory at best and this when the Germans *did* have the improbable chain of circumstances in their failure. Even a slight reinforcement of the armies in the Ardennes or one high-quality French force in the region skewers the Nazi plan wholesale and it becomes 1870 in reverse.
It was not Hitler who was cautious, it was his generals. Plan Yellow was his idea, he promoted the people who backed it, and stomped his generals into doing what he wanted done as he wanted done. For a reckless gambler this success to top all successes created many of the other problems that helped ultimately transform Hitler into the raving Omnicidal Maniac of 1944 who wanted Germany razed to the ground by his own party for failing him.
I think you are underestimating the French morale, and in particular command and control problems. Even using the original plan the Germans would have found a weak spot in the Allied line and exploited it. The French in particular simply were not capable of reacting fast enough. If your replace Gamelin, that will help. But, the paper superiority of the Allies simply disappeared in 1940 against a foe that could ruthlessly exploit any weakness. The Belgians, French, and British were simply unable to do the same to the Germans.
In addition, you can't ignore the fact of German air superiority. Allied air forces were ineffective until Dunkirk, conversely the Germans significantly disrupted Allied movements. That would not have changed regardless of the ground plan used.
Nonsense. The French problem was not morale, but hubris as far as psychological factors. Militarily their system was far too cumbersome and inflexible, strategically they were drawn into the wrong sector of the front on false information. They were flatly outgeneraled at a strategic level, but we can see from the massive losses sustained by Army Group B that the Nazi offensive of 1940 on the line wanted by Hitler's mealy-mouthed generals would have been a massive clusterfuck and 1870's perfect mirror.