I was thinking about developing a setting for Mythic Greece?  An somewhat accurate depiction of ancient Greece -- but with all the cool mythical stuff.  I'd like to use the D6 system for it's simplicity and cinematic feel.  Thoughts?  Feedback?

You might want to take a look at Legendary Quest.  I've put a lot of work into its mythological authenticity.  You might get particular use out of The Monsters of the Mediterranean and The Manual of Mythology.

There is a GURPS Greece sourcebook that is very good.

Also check out Zenobia at http://www.geocities.com/zozergames/zenobia.html. The game uses a d6 mechanic.

For a lighter touch, you might also wish to check out Mazes & Minotaurs: http://storygame.free.fr/MAZES.htm

I would merely warn you that Mythic Greece was not the same as ancient Greece. For example, take the Iliad. It is a mish-mash of several different technological levels (there are formations, but the story takes place in disorderly conflicts, the armor descriptions do not universally fit any single time period, etc). As such, it might be less stressful to focus on a Mythic Greek setting than one that is also historically accurate... or perhaps I am over-reading your intent a bit.

Also, there is the problem of which mythology will you follow. Is Eros the son of Aphroditie or is it a precosmic force born at the same time as Chaos, Gaia, and Tartarus? Is Ares a somewhat demented and perverted god or would you prefer the more Romanesq image that people tend to associate with Ares?

As for actually making it into an RPG setting, I cannot praise Legendary Quest enough, though if it has a short coming then it is in being a little too inclusive of information (it has been a while since I read it, but if I recall the system makes a difference between variations on creatures names, so that an Efreet is different than an Ifrit).

~Joel