I think you have the wrong perspective of Schema. Although it is sometimes useful to describe what links relate to (both externally and internally), Schema is most useful when content describes itself. E.g., it's not so much saying "This link refers to an Article" but "I am an Article". I very rarely markup links with Schema, as whatever page I'm linking to describes the content therein.

I don't know if there is a definite benefit to implementing Schema, but I've noticed that new websites I have launched seem to rank a lot quicker than without Schema markup. And, I think it looks nice, and provides a better user experience. There could be more guidance on Schema.org, but I think it does a good job. The real problem is getting into the mindset about what Schema is about.