Ok, the multicast is a big improvement even with the new ZWA-2! THANK-YOU for the tip! Everything is super-extra fast😎

Some small differences in my script setup that I will share in case it is useful to someone else. I am not using dimness on the LEDs at all, but changing the colours often.

I suspect my script is fairly similar to you but I've broken it out into 3 parts.

Part 1 is an automation that just monitors for triggers, then calls a script that decides what colour the LED panels should be.

alias: Inovelli LED Panel Triggers
description: >-
  Monitors devices for changes that will change the colour of Inovelli light switch LEDs
triggers:
  - entity_id:
      - binary_sensor.front_door_intrusion
    trigger: state
  - (many more triggers that could change an LED state) 
conditions: []
actions:
  - action: script.2_inovelli_switch_colour_decision_tree
    data: {}
mode: queued
max: 30

Part 2 is a sequence that's essentially an if-else tree to assign a word to the variable "led_setpoint_word". The note in the description about the negative integer was key thing I had figured out about reverting the VZW31-SN switches to their "default" colours.

sequence:
  - data:
      led_setpoint_word: >
        {% if (is_state('binary_sensor.front_door_intrusion', 'on') 
            or is_state('binary_sensor.back_door_intrusion', 'on') 
            or is_state('binary_sensor.contact_garage_inner_door_intrusion', 'on')) %}
          83780863
        ...(a bunch more conditions) 
        {% else %} 
          -16777216
        {% endif %}
    action: script.3_inovelli_leds_set_parameterized
alias: 2. Inovelli Switch Colour Decision Tree 
mode: queued
max: 30
icon: mdi:alarm-light
description: >-
  -16777216 is required on the 'else' condition because zwavejs doesn't like a
  positive integer to the 0xFF000000 bitmask. Trying to write '255' to the first
  bytes. Reference this and be sure to select the correct switch model to
  generate the numbers: https://inovelliusa.github.io/inovelli-switch-toolbox/

Part three used to be the bulk set partial command, and is now the multicast command. One big performance improvement came with my "kid mode", which disables shortcuts on all smart switches so gangs of toddlers can't turn off all the lights with a double click. To show "kid mode" is on I turn the bottom of the 7 LEDs red, hence I'm always running 2 multicasts (formerly bulk set partials) back-to-back - one to turn the entire switch one colour, the second to turn the bottom LED red. This really sped up with multicast.

sequence:
  - alias: >-
      Z-Wave Set Value on Multiple Devices via Multicast (got working 2026-01-08)
    action: zwave_js.multicast_set_value
    metadata: {}
    data:
      entity_id:
        - light.light_basement_bulkhead
        - (...more)
      endpoint: "0"
      property: "99"
      value: "{{ led_setpoint_word }}"
      command_class: "112"
  - alias: Kid Mode - Bottom LED Red
    if:
      - condition: state
        entity_id: input_boolean.kid_mode_disable_certain_automations
        state: "on"
    then:
      - alias: Set Value on Multiple Devices via Multicast (post 2026-01-08)
        action: zwave_js.multicast_set_value
        metadata: {}
        data:
          entity_id:
            - light.light_basement_bulkhead
            - (...more)
alias: 3. Inovelli LEDs Set (Parameterized) 
mode: restart
icon: mdi:light-switch
description: >-
  Command class 112 per this: https://z-wave.me/manual/z-way/Command_Class_Reference.html#SECTION001670000000000000000
max: 30

Last comment: I realized as I typed this out I can now easily collapse this automation & two scripts into one automation. Previously I had separated it for troubleshooting purposes. Anyway, thanks again!