As for the limited supply of fighters from England, that was due to the presumption (correctly I might add) that England could not afford to deplete its fighter resources in France. Decision was made to ensure that there were enough to fight the BOB.
Whilst the RAF were being reequipped with spits and hurris, at that time, there were still in fact squadrons of hinds (biplanes) in active service - which were upgraded just before the BOB iirc (I probably dont, but hey ho)
As previously stated, the french defence plan rested heavily on the Maginot line, which whilst impressive, doesn't move, so the hook around into Belgium was, at that time, a spark of genius. That said, had the disarray in the upper echelons of the French/English armies/air force etc been resolved earlier, it would have been a harder fight. Imo, France would still have fallen - blitzkreig being a new (and awesomely effective tactic), and there was not enough space to trade for time to resolve how to beat it - unlike in Russia.
Wurzel