No, not really. You don't need the 'unicode-range' attribute though, nor the format part of the src.
iBooks is a little peculiar in font embedding. You need an additional file in your META-INF folder, called com.apple.ibooks.display-options.xml. For more info see the excellent article
here.
This being said, not all fonts render correctly in readers. Some fonts just won't always work. Some don't in ADE and some don't in iBooks. Try if it works in ADE. If it doesn't, try another font.