I'd prefer a manned lunar operation, too.
At least a human presence could be used to possibly repair any punctures,
or replace the punctured material.
It won't be "spherical" when inflated, just as some balloons, when inflated, are designed to take other
shapes besides a sphere [i.e., football-shaped, sausage-shaped, etc.]. The inflatable radio-telescopic "dish" should actually be double-parabolic, "saucer-shaped" when inflated, with one half being radio-reflective.
cheers.
Jacob