I read a bunch of WN chapters (100+) through MTL, and I'm still not sure if he's incredibly strong, or relatively weak but with a variety of incredibly strong skills and good usage of them.
I thought he showed his stats to others at some point, and they also don't think they're very good? But he barely ever has a difficult fight while all of his classmates struggle while fighting in large groups? Between my confusion and the later chapters (of which there are over a 1000) being nocturne (age 18+) chapters, and not conducive to google translate, I kinda gave up on the series. (Google Translate won't translate nocturne chapters, at least as far as I can tell.)
I think I'll keep with the manga though, but I do feel like they're skipping details. I think F rank magic stones are divided into at least another 10 subdivisions, which isn't clarified at all here.