Choose an air-to-water heat pump with a lower supply temperature?

We are in the process of planning our own home. It will cover 135 sqm, have 20cm thick insulation and triple-glazed windows. According to our architect, the house will be eligible for funding under Kfw 70. A ventilation system with heat recovery function is planned. For heating, an air-water heat pump with a flow temperature of 40 degrees is to be used. Would it perhaps be more sensible to buy a pump with a flow temperature of 35 degrees for an additional cost of 1500 euros? Is it worth it? What electricity consumption should we calculate annually?

Have an energy consultant calculate this for you; you cannot simply answer "Yes, it's worth it" or "it's not worth it." The overall situation is important.