Hey, where you want to set the 19.5°C? I have no problem with the slider in the automation itself. When you mean the comfort temperature, than you have to edit your input helper to allow 0.5 steps.
Do you have another automation that sets presets? Or maybe an automation of your bridge? In my opinion the preset is persistent until you set a new one. But If you want to extend the blueprint your right in the action section:
action:
- service: climate.set_preset_mode
target:
entity_id: !input 'heating'
data:
preset_mode: 'permanent'
- service: climate.set_hvac_mode
target:
entity_id: !input 'heating'
data:
hvac_mode: "{{ mode }}"
- condition: template
value_template: "{{ mode == 'heat' }}"
- delay: 3
- service: climate.set_temperature
data:
entity_id: !input 'heating'
temperature: "{{ temperatur | float }}"