Yes you are vastly overestimating German strength and Czech weakness.
Not really. The annexation of Austria had opened up the Czech southern flank to attack, and it's border defenses were never as good as claimed. Like almost all pre-war defenses they lacked depth, only 5km at their deepest, 100 meters as their narrowest. Key industrial areas were also very close to the border, so any fallback would also have crippled Czech war production. Even worse, in 1938 the fortifications weren't even complete, and they lacked heavy artillery. The line was manned largely by maneuverable-incapable defensive divisions, and lacked the essential ability for local and large scale counter attacks, which was proven in WWII to be required for a sufficient defensive line to be manned.
There was also the very real threat of Poland and Hungary taking the opportunity to seize their claims in the disputed border, stretching Czech forces even further.
Maginot line was irrelevant to France invading a defenceless Germany. By defenceless I mean all German troops in the east fighting Czechs. Just like what happened with Poland when Germany had the bonus of Czech war loot to use. yeah French didn't attack then either but that was a problem with the leadership not due to lack of forces.
Except the French didn't have any offensive plans. France was incapable of helping the Czechs because the French military hadn't drawn up any plans to attack Germany in a meaningful way. Public opinion in France was also extremely against another war in Germany, not hard to understand why given the million plus casualties the French had sustained. If the French government had pursued hostilities with Germany, they would've faced immense opposition from home, and would've struggled to meaningfully impacted the effort.
Disagree with you there completely.
If the English hadn't cave at very best Hitler would have had a divided and unenthusiastic Military at worst he would have been removed and no war.
Again, not really.
"For its part, the army tried to use its control of personnel assignments to affect the balance of power. Fritsch and Beck believed they could torpedo the War Ministry's ambitions [for war with Czechoslovakia, which they had been ordered to start planning in 1935] by filling key positions with officers who would defend the army's point of view. For example, in the late summer of 1935 Beck went to the chief of the Army Personnel Office, Lieutenant General Viktor von Schwedler, and said he needed an officer to be Reichenau's replacement as head of the Armed Forces Office. The officer should be a good administrator, Beck added, but not too bright, and someone who would not sell the army out. Schwedler said he could only think of one man: Brigadier General Wilhelm Keitel. Beck took the suggestion to Fritsch, who nominated Keitel to Blomberg. Blomberg accepted, and Keitel took up his post on October 1. However Keitel soon demonstrated that he believed just as firmly in the principle of centralized Wehrmacht command as Reichenau had, and he outdid Reichenau in loyalty to Hitler."
-Geoffrey P. Megargee, "Inside Hitler's High Command," p.34
And to show how serious a miscalculation this was:
"[Keitel] quickly became convinced of Hitler's genius as a political and military leader. 'At the bottom of my heart I was a loyal shield-bearer for Adolf Hitler,' he told Allied interrogators after the war, 'my personal convictions would have been National Socialist.' Moreover he fell completely under the spell of Hitler's personality, and his way of avoiding conflict was to agree loudly with everything the Fuhrer suggested."
-Megargee, p.41
Most of the Wehrmacht approved of what Hitler was doing in general, or at least wasn't willing to rock the boat given Hitler's popularity.
Either way they didn't have the arms/armaments to win quickly against the Czechs and if France (which did have a large army) and the Brits who were building forces attacked it would have been bye bye Hitler and no WW2
Britian didn't start major rearmament until
after Munich. And what makes you so certain France was going to save the day? How would they have done so?