I wouldn't suggest burying your wireless IP scheme under a second layer of private IP addresses. It will come back to bite you in the ass.
(Public IP Pool) <-> [Cable modem] - (Private IP Pool) - [Wireless router] - (Private IP Pool)
The proper method would be to use something like this to create a flat infrastructure. I use these APs in my house and love them. (not affiliated as anything other than a satisfied customer)