If you insist on mucking with the global environment, you can always add:
_G[ ... ] = M
People sometimes prefer to write all of the functions as locals and end with:
exportedFunction1 = exportedFunction1,
exportedFunction2 = exportedFunction2,
exportedFunction3 = exportedFunction3
This allows you to see all of the exports in one place but it also requires writing the names twice. If you don't trust your spelling, you can help a bit by wrapping the right-hand sides in asserts (or using a lint that hunts for global reads).