E-mail encoding and mixed html/text content

1. Is there a way to force the text/plain part to be UTF-8, format=flowed, and content-transfer-encoding set to base64?
   
2. Is there a way to force the text/html part to be UTF-8, quoted printable?
   
3. Are there any more "control macros" other than {unwrap} for e-mail?
   

-joho