tl;dr, but I wanted to point out that acting quality is discernable reguardless of knoledge of language with one simple point.
Moon Child. Hyde is a laughable actor. End of discussion.
As for American V/As making more than seiyuu... Have you ever TALKED with an American V/A??? They have to hold down real acting careers, do their V/A work, AND keep a part time job just to stay afloat! Seiyuu in Japan have much more popularity and can spread themselves out to working on soundtracks and audio dramas, so they don't have to hold down other jobs.