FIOS install

I am getting a Verizon FIOS install(data and phone) soon and plan on doing ethernet to a Asus RT-N66U. Location is FIOS ready. I had a couple question that I was hoping someone who has FIOS could give insight on. 

1. Are there any specific settings on my router that help with performance? MTU? DNS? 

2. What are FIOS IPv6 settings? Available in RI? Native DHCPv6? What IP block?

3. What are the general metric to check for at the ONT? I know it doesn't have a web UI, but what would a technician check during a install?

4. Any pro/cons to having a battery backup? I have one currently but was considering removing since possibly old. Does ONT run off battery or AC during normal function?

Thank you for any input you may have.

Hmm, guess this forum section is DEAD huh? 

Quick update. FIOS installer was a idiot. Didn't know what IPv6 even was (never mind if they had it) and seemed more concerned explaining his organic diet and lime disease(BTW, lime grass is good) then talking about the service. Drilled a hole in my wall without asking and when we had agreed to try to use a exsisting outlet.  His excuse "It's just one more hole". Spent 10min trying to release IP from gateway.  3 hours after install internet went down. Phone support was even more idiotic. Didn't even understand I was using my own router. Kept telling me she was "going to send a signal to my router". I was like "No your not". My guess is still something to do with the IP assigned to the gateaway and the ONT needed a reboot. Rep had NO IDEA what caused it. Seems like the strike drained the collective IQ of Verizon support.  As someone who works in support, I was not impressed.

Bump? Anyone? Guess this is outside the knowledge of this forum? Seems the networking section in general is pretty weak. 

For anyone curious, here are some lessons I learned:

1. FIOS support does NOT like using ethernet. They see it as the customer being "picky" and will automatically assume any problem is related to using ethernet. I feel this is due to a lack of training outside their small confines of understanding and a push from corperate to rent more gateways. Basically, if you pick ethernet, FIOS will try to hit you in the nuts any chance they can get.

2. FIOS caches the IP address to a MAC address. If your DHCP lease runs out or if you get a new router, you have to call them. They won't admit this however, because they don't want the call volume. Instead, they say you "may" have to call in. 

3. Don't change from using their gateway to ethernet. Their provisioning system is ackward and clunky, taking up 2 days before my connection was stable. My internet would lock up (phone still work) and I would lose my IP lease. The only thing that would correct it is a reset of the ONT. I think this was caused by the system still thinking the gateway was assigned to my account and not accepting a bridge from another device. Pick one or another before install, DON'T switch after the fact if possible.