When I worked in Europe we had to take a 'voice' course as part of the training. I am a native English speaker and scoffed at the idea. Until I actually started flying around Europe to 20 different countries with 20 different languages and accents. The standardization that existed there allowed for far less confusion.

I would advocate the same standardization here in the US. It really does reduce confusion if you are saying and listening to the same things for the same procedures.