Garner's focus is on usage, not grammar, so for a usage linter, this doesn't seem like a big problem. Is there an accessible, comprehensive, easy-to-read guide

Garner's focus is on usage, not grammar, so for a usage linter, this doesn't seem like a big problem. Is there an accessible, comprehensive, easy-to-read guide like Garner's Modern American Usage that's considered more accurate? There don't seem to be many options. (I have a copy of GMAU and enjoy it, but mostly for discussion of usage, not the details of grammar)