Are any of these devices Z-Wave? If so, it might be worth checking into your Z-Wave network health from Settings > Z-Wave Details. There aren't any hard rules about what's 100% "bad" based on any data there, except that "ghosts" (at least for powered devices) are generally bad news, which could be anything without "Route" information shown (unless that's just empty because there hasn't been any communication since the last restart) or an associated "Device" (or one that doesn't work, though that could be due to other problems). You can find more information on the stats here: Z-Wave Details - Hubitat Documentation.
Zigbee networks can certainly have problems, too (e.g., do you have any smart bulbs paired directly to the hub? how many repeaters and non-repeaters total?) -- but they seem to be less picky. LAN/cloud have their own concerns but most people don't have as many of those devices.
Anyway, just something else that could be worth looking into if you haven't. Metering can certainly be helpful, too, however.