I’ve noticed that after removing the various Google voice/video devices across my network (I don’t remember why) that I can’t no longer bring them back. The same applies for my router.
What are the ramifications of removing any of the above and is it possible to have Home Assistant detect them again to re-add them in?
There should be none. I test stuff all the time. Remove, reinstall should work like any other operating system. If there is something that missing in integrations. Go to the integrations page at the top right there is a filter icon. Click and choose show ignored and disabled integrations.
Thanks for the tip @Mikefila
I checked that and don’t see my two nest wifi speakers, my chromecast, or my nest hub. I think I’m just going to go from scratch again 
(it’s good practise for me).