Hi all, looking for some installation advice please!

I'm new to mesh WiFi and can't claim to be hugely savvy on router set up either. 
 

I live in the UK and have my broadband supplied through Vodafone (Superfast 2 Fibre) which brings in download speeds of ca 60 mbs and around 15mbs upload. I have the latest Vodafone broadband hub. 
 

I recently installed a set of 3 Deco M5 units. I followed the set up instructions in the app, connecting the main Deco to the router as instructed via Ethernet and then paired the second and third units too. 
 

The default installation settings that the app prompted me with were Dynamic IP (as opposed to PPPoE) and Router mode (as opposed to AP mode).

Once up and running the system does seem to be operating as hoped, I now get a better WiFi coverage than before and the speeds seem fairly consistent. I have however had an issue with line dropouts (DSL line drops in the Vodafone router status log) and I'm therefore wondering if my Deco system is set up correctly. 
 

Can anyone please advise if my configuration sounds correct or whether I need to change any settings such as Dynamic IP or Router mode? Are there any other setting that I ought to change from the factory defaults on either my Deco units or my Vodafone hub? 

In addition is it good practice to disable WIFI on the existing router (in my case the Vodafone hub)? 

Any advice would be hugely appreciated.