Service timer.set (or other way to modify timers before starting them)

Feature Requests
1

I would like to request a feature that allows users to set timers via service, ideally even timers that had not previously been created.

Example

variables:
  name: fan
  duration: "00:25:00"
service: timer.set
data:
  target:
    entity_id: timer.{{ name }}
  data:
    duration: {{ duration }}

This would create timer.fan and set its duration to 00:25:00. This would allow users to pass variables to this, or alternatively use an input_number entity, for example

input_number:
  fan_minutes:
    min: 1
    max: 300
    step: 1

# (...)
  service: timer.set
  data:
    target:
      entity_id: timer.fan
    data:
      duration: 
        minutes: input_number.fan_minutes
2

Let me start by saying I agree this should be part of standard HA.

There is a an integration that can do part of what you want

3

I’m confused by this sentence.
Because I set my timer duration all the time based on input_number
Like, as exemple, in this automation (extract)

  - service: timer.start
    target:
      entity_id: timer.coucher_des_enfants
    data:
      duration: '{{ int(states(''input_number.duree_coucher''), 10) * 60 }}'

I understand that this set the duration at start.
Is it the feature that you guys were looking for? Set it way before starting it?