the way I view Mythics is that rather than changing the character in any fundamental way, it represents the strongly ingrained destiny of the character. This is the thing I really like about Mythic path vs. Epic. Epic characters are already extremely powerful beings... that just get more powerful. There's no sense of wonder, there's just endless optimising and hack-n'-slashing.
Think of a Mythic fighter as Hercules, or Theseus on their Day One. You get to start from grounds-up, following a hero's journey from the very beginning. And we all know that this journey is not like any other... because in the character sheet itself, he is DESTINED to become a champion!
You'll get to fight not epic force dragons or demiliches but Mythic Lions and Boars, wrestling the most extraordinary versions of mundane creatures that themselves are of Mythical proportions.
That 'Greek Mythology' feel, is what gets me excited about Mythic Adventures.