"optimal" network setup?

Hi All -

First time discussion starter! 

I am by no means a networking expert, and I understand this topic may have been discussed previously, however I have a some questions and issues needed on my specific setup. Anyone from the entire community's assistance will be greatly appreciated. 

Home

• Size: 1,700sqft
• Type: Townhome - 3 levels
  • 1st Floor - office floor / garage
  • 2nd Floor - kitchen, living room, dining room
  • 3rd Floor - 2 bedrooms (network devices are here)
• ISP: Xfinity 1000mbps

Products

• Netgear CM1000 Cable Modem
• Netgear Nighthawk AC1000 Router
• Netgear GS105Ev2 Prosafe Plus Switch
• Google Wifi Gen 1 (5 points)

Other Products

• Apple HomeKit
• Arlo Pro 2 - (4 cameras)
• Philips Hue Bridge

Currently I have this as my hardwired setup:

1. ISP 1 >  Modem > Nighthawk AC1000 (SSIDs Broadcast Off) > Network Switch > Google Wifi / Arlo Hub / Hue Bridge

(before today I had the Google Wifi plugged in directly to Nighthawk, just trying something new haha)

Issues:

1. I want to get your (Community) insight on the "best" set up for optimized usage - currently Google wifi says I only get 90mbps download / 19mbps upload)
2. I'd like to add a VPN (using ExpressVPN) to the entire network - for the sake of protecting my data and usage
3. I'd love to be able to add the Arlo cameras and Philips Hue bridge/lights to Apple Homekit (currently I can control the cameras and lights through the respective "Arlo Secure" and "Hue" apps through my iPhone). However I can't discover either device/product when trying to add them to HomeKit

Again, I'm no networking expert, but I do consider myself a learner and did my best to get to my current setup. Any advice is greatly appreciated.

Thank You.