When i had a lott on secure, i would get, for instance, temperature, but not lux.
So no, to many devices on secure, and Homey just misses stuff and slows down heavily.
After many years experience, my serious advice would be: Befour trying anything else, re-include (some/as many as possible) devices non-secure. If than problems persists, take further steps.
But for me, and many more, there were enough topics about it in the past, secure was the big deal: Homey cannot (or could) effectifly handle to many secure zwave devices.
I had issues with devices when i had 20 secure. Now i have a little over 70 zwave devices, about 10 secure. Everything works “perfect”.
You can add different devices non-secure.
A few years back, Fibara could be unsecurely added by selecting the Walli-socket-thing, and it would add the correct item (always tries that) but unsecure.
But now-a-days, most devices from Fibaro are automaticly added as non-secure(!), this to resolve the issue with to many secure working modules.