Mail and changing default font (MessageFont, Universal Mailer, etc)
So now that we're on Mail 6 under OS X 10.8, are there any good options to set a default font for outgoing messages besides manually doing it for each individual message?
MessageFont was released late in the Snow Leopard era and worked reasonably well, but new messages / replies / forwards had to be created by keyboard shortcut, and Lion / Mountain Lion interfered with full functionality.
Universal Mailer is okay, but it requires that there be existing HTML elements to the outgoing message, and I can't figure out how to force it besides having an HTML signature since Mail will send in plaintext unless it absolutely has to use rich text despite saying "compose in rich text" in preferences. Then, when using HTML signatures, there is a discrepancy between font size of the signature and font size of the message.
Anyone thought of a solution for all this?