I love "Fantasy on a Theme by Thomas Tallis", and this excellent description by Steve Schwartz on Classical Net who says "I've known this work for almost forty years. I treasure it. I'm quite aware that understanding the skeleton says very little about the miracle of its life. If I knew how that were done, I wouldn't be writing prose."
RVW has also done great things with Greensleeves. The first time i knowlingly heard RVW's works was a mass sung by the Detroit Concert Choir
Great sounds from his EWI and Mighty Serge synths. His works are featured on Western Spaces CD. I have the first version. (A later version of the CD replaced a couple pieces, but kept Braheny's stuff.)