Unfortunately there’s no easy way to map out your mesh within SmartThings. There is some discussion here:
I live in a similar single story home and I have at least one or two pocket outlets per room along with a few smart switches. One reason I have so many is because I run both Z-wave and ZigBee devices throughout the house. In this way, I’m pretty certain that I have a fairly strong mesh.
If you are running mostly ZigBee then they will be using the crowded 2.4ghz frequency so there is possible WiFi interference. Make sure your hub is at least 6 feet away from your router. There are also tools that can check what channel your WiFi is using so it might help to move your WiFi channel. And to make things a bit more complicated, sometimes neighbor WiFi signals may overlap as well.
If your Hue lights are connected through a Hue hub, then they will only repeat amongst themselves. In anycase, light bulbs as repeaters have not always been that reliable or trustworthy.
Yes, I know how frustrating things can get when they don’t work right. Hopefully you’ll be able to track down your problems and get thing running smoothly (although with ST, there always seems to be hiccups along the way, part of that whole cloud architecture that can be flakey sometimes.).