I know this doesn't address many of the issues with a module system in arc... but there is currently an import.arc file in the arc-wiki that has a few interesting points.
In the current import.arc, when you import a module, the name of the module gets set to a macro which allows you to access functions in the module via composition. Thus you get to use : rather than another arbitrarily chosen character. I just thought that was kind of cool.
Maybe there is a problem with just simple composition that doesn't scale when applied to a full blown module system. But if you could incorporate this into any ideas currently going around, I think it would clean up the syntax for accessing internals of a module at the very least.
