You can look for other apple juices/ciders with low OG and blend if you want to keep max apple characteristics. But you'd need lots to bring the gravity down, because its probably at least 1.03 and up.
Water will bring it down, but you may as you said, thin it out too much.
did you want a sweet, semi sweet cider? If so are you averse to using something to kill the yeast @ 7%?
Other than that cold crash re-rack should get you where you want to be, just keep it cold and it will be in stasis. Gives you incentive to drink through your supply faster