To me, there are several problems with this approach:
1) Britain in 1938-39 was already outproducing German in fighter aircraft; and clearly had a massive lead that Germany could not overcome in surface naval ships. Britain would never be able to match Germany's land force size.
2) When Hitler went into the Rhineland, the neighboring nations of France, Czechoslovakia, and Poland, plus Britain, outnumbered Germany 140 divisions to five. Even when Hitler went into Czechoslovakia, the Allies vastly outnumbered the Germans . . . without Russia.
3) There was absolutely no military advantage to be gained by waiting.
Yep, the opportunity to stop Hitler was there, but it was lost. And there was an organized group of German generals who were just waiting (and hoping) for France to move. Hitler would have been humiliated, and his own generals would have deposed him.
But France did not move. The Rhineland did not seem worth it.