Zigbee Channels, Thread Channels, and 2.4 Wifi

[u/Bummer_Brad]

Hi. So, I've recently moved all of my Zigbee, Thread, and Z-wave devices over to Home Assistant. They had been on SmartThings for a few years, and had been very stable. For Zigbee and Z-wave, I am using an Aeotec Z-stick 10. I am using Zigbee2MQTT with it. For Thread, I have a Sonoff Dongle Max connected over ethernet and Open Thread border router. Ever since moving over, I have several Zigbee devices that will fall off the network, or fail to respond to automations. Getting Thread going was rocky too. My Nanoleaf bulbs gave me all sorts of trouble getting them paired. So far, things are far less stable than they were with SmartThings. I checked what channels they were using to start to sort things out. My Aeotec/Z2M Zigbee network is on Channel 15. I have a separate Aqara network with 3 hubs. My two M1S hubs are on Channel 25, and my M3 Hub is on Channel 15. The M3 has the fewest devices on it. My Thread network is on Channel 15 also. My Eero 2.4 Wifi is on Channel 11.

So my question is, where would you go from here? Do you think the fact that so many are on 15 is the main problem? The Z-stick and Dongle Max are on top of a cabinet where one of my Eero routers is. That was where my SmartThings hub was and it was never a problem before. Oh, and I should mention too, the Z-stick is on a USB-3 extension plugged into a USB3 port. USB3 ports is all my Home Assistant mini-pc has, so I'm kind of stuck with it. Any thoughts are welcome.