Dual WAN question

I have an Arris SB8200 modem with 2 Ethernet WAN ports. Can I use the load balance in dual WAN to use that 2nd WAN connection? No sense using fail over as if the one fails then both will. Will this give me any benefit?

Also, I am using the 4 LAN ports on my AC3100. Should I use the USB 3.0 port to connect or get a cheap Ethernet hub? Guess I should have sprung for the AC88U.

I'm sorry to pester the forum with this. Having trouble finding info both here and on Asus' support site.

Thanks in...

Dual WAN question