This may seem like a small issue but it is a death by a thousand cuts situation.
When uploading a single module to the library I often forget to name it MainModule before I publish and the require errors out. I think if the require() loader automatically detected that a single module file would be the main module, it could help prevent this. Having things named MainModule in general isn’t a terrible idea, however it does more harm than good if you upload a single ModuleScript, forget to name it, and then have to go back and fix it.