There must be some 'magic number' of devices where the "cranky" route discovery requests becomes an issue. I'm a ZWave house and have barely dabbled in Zigbee. I have 5-6 Iris motion sensors, both v2 and v3, a Peanut plug for routing and a pair of Iris Power plugs for christmas lights, that have been powered off for weeks now. My initial foray into Zigbee was back in early November and I haven't detected any glitch. The very first v3 motion detector is stuck to a ceiling and I'd remember having to touch it
At the low end then, I have 7 active Zigbee devices, not exhibiting the "cranky" route discovery requests syndrome. 30 is enough, I think you're saying, to see it?
Until this is fixed, and I'm fearful its a Zigbee radio update * to fix, I'd like to parrot better than average responses to messages I see.
( * The SiLabs Ember 3581 used on our HUSBZB-1 Nortek supports both the Zigbee PRO Stack Profile (for thousands of devices) or the Zigbee Stack Profile coded onto/into the SOC. ** Implication being: the stack is on the stick, independent of where the stack (source) originated. )