There is no reason to use IPv6 on a home network, there is no way you are exceeding the number of devices that IPv4 will allow, not on that router. Your modem needs to be able to handle IPv6 addresses to receive data from the internet. The router will then distribute that data using IPv4 addresses to your home network.
edit: IPv6 does not speed up or stabilize your connection. It's just a addressing scheme. It provides no benefits on home networks. And likely only adds complications and compatibility issues.