Xb6 Gateway replacing my Cisco DPC3942T and would appreciate any preparation advice.

Xfinity emailed to tell me my 4 yr old Cisco (Xb3 ) Gateway was being replaced for free with their Arris TG3482G (Xb6) gateway and will be shipping out a self install kit. I’m fairly tech savvy, but no Steve Jobs, and would appreciate any advice anyone who’s done this might be so kind to offer; beyond downloading the manual, reading the setup instructions and utilizing the APP.  We normally use about 1TB monthly and it’s creating issues with the older Cisco. ( Though it’s been a relative champ for me for the last few years. ) 

Here’s a picture of my current usage and average clients connected on a normal day.  I’ll provide a detailed list of my Comcast Equipment and attached clients to give a clear picture. 

XFINITY EQUIPMENT:

Arris XG1v4 HD DVR Main Box hooked up through COAX 

(2 QTY ) Pace XG2 Boxes utilizing the X1 Cloud DVR in guest rooms. 
Cisco DPC3941T Gateway DOCSIS 3.0 attached to the drop with a Highly Shielded Top Quality Coax. NO TELEPHONES hooked up, nothing plugged into Ethernet Ports, Local HotSpot Disabled- basically used as a Router.

Pretty straightforward setup  utilizing a blended 2.4/5 ghz SSID. 

i believe we have the 600mbps Blast package and speeds - until recently, have always been decent and sufficient. 

Xfinity will be sending me the Arris TG3482G Gateway which I understand is faster, utilizes DOCSIS 3.1 and as I recall, has a Max Client Limit of 30 on 2.4ghz, and 75 on 5ghz channel; plenty for us. ( I do not recall the Max Client Limit on my current CISCO, but would guess 25-30 MAX clients each channel.) 

So, as previously mentioned, average data use monthly 850mb ~ 1.3 GB +/-.  Wifi coverage throughout our home has always been excellent as it’s centrally located.  

Devices / Clients in heavy rotation in our home are as follows: 

(1) LG 65” OLED running from the X1 main box through my WiFi enabled Onkyo surround sound receiver as this is our most watched TV. And don’t ask, but yes, we have more Streaming Services than I can recall and NORMALLY Stream every show we can via the WiFi as it allows us to take advantage of Double Vision, Dolby ATMOS, HDR and just generally provides a far superior picture than streaming these same shows through Xfinity’s XG1v4 HD box, which does not support most of these features. 

(2) LG 50” Midrange LCD TVs in guest rooms which are both SMART as well as hooked up via the Pace XG2 Boxes. These TVs are used infrequently. 

3 Apple iPad Pros, one used heavily. 
3 Apple iPhones which use less than 1 GB of Data Monthly

1 Roomba used weekly

(2) Fire Sticks - used infrequently. 
and a few odds and ends using little data, and of course, any devices carried in by friends, family, visitors, etc.  

Do not utilize MocA, Security Systems, Cameras, Smart Home tchatckes, No Nest Thermostat or Appliances with WiFi access.  So, the old CISCO has done well until recently, and hopefully this new Xb6 Gateway easily outperformed the old one.   Here are my questions for anyone with time to offer advice. 

1) Am I correct the Xb6 using DOCIS 3.1 and that should both increase speed throughput significantly, as well as offering a better experience in a neighborhood with a heavily used NODE on weekends?   

2) Would I also be correct that the Xb6 gateway’s ability to handle far larger client loads than my current CISCO and that should allow far more devices to be served simultaneously?   Might it also experience less interference from other household appliances ( e.g., microwaves, etc. from creating problems with our devices on the 2.4 Ghz devices, which happens from time to time?  Any other obvious benefits I should be aware of? 

3) What are the Top three MOST LIKELY issues I’m likely to experience, and any advice that worked for you? 

4) I generally log into every Gateway when I first purchase simply to change the ADMIN and PASSWORD they all seem to come with as a simple precaution, and for reasons unclear, this always created problems on Comcast’s end which resulted in me having no WiFi until they reset it to factory remotely.  Any advice when/if I log in as ADMIN or suggestions or settings to consider?

Finally, thank you kindly for taking the time to read this and any helpful input you can offer me. It’s much appreciated.