Xiaomi plugs go offline, taking other devices with them

[sh00t2kill]

Note: I originally posted this on the home assistant FB page, but figured this is proabbly a better spot for it!

I have about 40 devices, 5 or 6 of which are smart plugs acting as router's. Most of them are aqara. Motion, door, temp, and smart plugs.
Zigbee channel is set to 20.
I am using a LAUNCHXL-CC26X2R1 as a coordinator, after upgrading from a CC2531 which gave me issues once I hit about 20 devices. It was the only thing I could source during covid when the 2531 gave me grief. For a while, this solved my issues.

I've got devices just randomly going off-line. A reboot / repair will bring that device back online, and for few days everything will be fine, only for it to happen again.
Is the coordinator I'm using no good? Will changing to a zzh! give me a better outcome? Any other levers / config things I can tweak?

z2m zigbee map attached.

Are the ZNCZ02LM plugs just crap and I should replace them with something else ?
Ive got both a LLKZMK11LM and a ZNLDP12LM, and neither of those exhibit this behaviour

The devices that dissaapear are further away than others .. the ones that stay online are generally closer to my coordinator. Unfortunately moving it isnt sometihng i can easily do as its physically connected to my NUC protected by a UPS.
Sometimes they eventually come back on their own, or will toggle state once/twice but not report back to z2m.

[sh00t2kill]

I think I might have been reading the map wrong.

If i select only "isParent", it seems to me like every plug is using a single other plug as its parent, rather than directly to the coordinator.

Am i reading this correctly ?