I especially like a fireplace with a slow-reacting underfloor heating system. During the day, when you are moving around, the 21 degrees Celsius that the underfloor heating is set to are sufficient. But in the evening when sitting, that's not warm enough for us. So in winter and during transitional seasons, we often heat additionally with the fireplace in the evening. We wouldn’t want to miss it.
I know , we both have already discussed this here once and I don't want to claim to be more right than others; as is often the case, there are different opinions and especially sensitivities. We had it as you described, and for us it was not comfortable, rather annoying. We set our "normal" comfortable temperature with the underfloor heating (a bit lower, because we don't like overheated rooms) and when the fireplace was on with its considerable output, it quickly got too warm for us and even in winter we opened the window. The underfloor heating gave us "our" temperature, so why should the fireplace make it warmer than comfortable? Or we needed it because it was too cold beforehand, but then the underfloor heating was set too low. The "problem" with underfloor heating is its inertia, which is why we didn't want it anymore. In the new house, for example, we have large window areas and even in winter (not on the freezing cold days) it gets pleasantly warm from 9 am thanks to the sun and without any heating, in the afternoon it cools down again and we heat a bit with the fireplace (or infrared or air conditioning), depending on what we need at that moment. Underfloor heating could not react so individually and quickly, for us it was often too warm. But I also often read about standard temperatures in rooms that would be uncomfortable for me, so as you said, it can be individual. We also have a different usage profile or lifestyle, and that's exactly where builders should pay close attention to how their very individual sensitivities are, because fortunately no heating type can cover all cases. For example, my wife is not home during the day and I am mostly in the open upper floor when I am home, and then often there is no heating running on the lower floor except occasionally where I am upstairs. It just has to fit every application case, I simply think you should really consider this critically, because it is an expensive pleasure for a nice gimmick that also brings spatial consequences, as here. Acquaintances also have a nice fireplace but use it max. 3-4 times in winter. In that case, I would know how else to spend my money for comfort gains in the house. In this respect, I do not contradict you, since it is like that for your feeling, but for me it just didn’t fit at all and the nice, expensive fireplace always stayed off.