+1 on a proxy (with read-only attrs) for everything but __name__, __file__, and __path__ (which can all be different than the spec).  Ideally __name__ and __file__ would be read-only too but they'd have to be stored somewhere other than the spec (e.g. on the proxy or module object).  __path__ could be similarly proxied but would at the least have to be mutable.

The nice thing about such attrs is they wouldn't show up in the module's __dict__, assuming they are properties.

The only catch I see is where the module's code sets one of the attrs.  Would the proxy (or import machinery) pick those up, or maybe for some of them emit a warning or fail?

We could also skip the proxy and add the properties to ModuleType directly, no?