Chuck was obviously a much more technical guitar player. Hetfield was a vastly better vocalist and lyricist. I feel like Chuck Schuldiner vs Dave Mustaine would be a more relevant comparison, since they're both vocalists and lead guitarists and the main men of their respective bands.
Dave is garbage. Garbage vocalist, garbage lyricist, garbage songwriter, garbage lead player. Sure, he's flashy and technical but it's so fucking boring. He wrote some classics back in the 80s, great, who the fuck didn't? He's accomplished nothing since The System Has Failed.
I agree with pretty much everything there, although Chuck was a pretty good lyricist himself.
Chuck vs Dave would be hard as fuck for me. Both great guitar players, but Dave clearly wins there. He's also a better songwriter. They're pretty even in the vocals and lyrics departments, if anything another slight edge to Mustaine in both of them ... although both bands did have some silly lyrics early on.
Chuck vs Dave would be hard as fuck for me. Both great guitar players, but Dave clearly wins there.