Versatile Thermostat to control backup heating

[b0g3r]

Hiii! I'm not sure if this something that is usually solved by VT or outside, but I need an advice / solution

I'm in EU, and I have two AC units in two rooms out of four; as well as one gas boiler connected to radiators in each room, corridor and bathroom. In winter I would like to prioritize heating with ACs, because it's more energy efficient / cheaper, but I still would like to keep temperatures in remote to AC rooms on a nice level, which would require usage of gas boiler from time to time. I have full control over ACs (heating/cooling, target and sensor temps, fan speed) and over boiler (target flow temp), a temperature sensor in each room, as well as outside temperature sensor.

My initial idea was to:

• Set each ACs to target of thermostat, supply temperature of a room where AC is located. When room is heated, AC will switch off, even if other rooms are not heated yet. Two distinct climate entities
• Set gas boiler heat curve based on target of thermostat - some offset (e.g. 1℃) and average temperature of all rooms. One generic climate entity with automation on top of it for offset and heat curve.
• VT to control them

However, when I read more about VT, I understood that maybe my case could be solved by representing gas boiler flow temperature as a valve. Am I overcomplicating things? Is this something that someone in community already did? What would you advice for my use case