The points and counterpoints have already been made countless times on other threads, but this thread is really not about such opinions. Instead, this thread is more about learning the specific details at the specific points in history while speculating about the better Maginot designs (that does not include not building it).
Better than what it actually contained as in more? But considering the Germans went out of their way to avoid having to tangle directly with it (until the French were defeated and it was relatively safe to do so, when Goebbel's made a nice propaganda film about it), taking some considerable calculated risks in the process, that seems entirely redundant.
The Maginot as was didn't need any improvements. Which means the "better" bits would either have to be about its extension to cover more frontage, along the Belgian border, or more general changes to the French campaign plans NOT involving the Maginot Line?