founders edition is basically the "reference" version of the card. so its quite pointless to get them really since they cost $100 more. and offer no benefit, and as ive seen from people who have the founders edition 1080, the cooler is quite bad. so yea better wait for the custom versions of the 1080 to your liking.
and the GTX 1070 is a whole new card it self. a nerfed version of the 1080. but quite a powerful card, more powerful than the Titan X/980 Ti.