Massive house vs timber frame construction method?

Solid wood has already been mentioned. That is still interesting for us, but we are building with a flat roof. And there, the civil engineers in our circle of acquaintances, even those specialized in wood, tend towards solid construction.

Sometimes advice is given based on what is familiar and not against prejudices out of convenience. Of course, there are plenty of problem-free airtight flat roofs on wooden buildings. We even have a green flat roof section on the wooden house. Carpenter and roofer are one company.

Sometimes advice is given out of convenience towards what is familiar and not against prejudices. Of course, there are plenty of problem-free dense flat roofs on wooden buildings. We even have a greened flat roof section on the wooden house. Carpenters and roofers are one company.

The same applies to us, it has to be an extensively greened roof. I would do it with wood, but since I can't find a company in the area that offers it to me all from one source... that already smells too much to me....

We also build with flat roofs. Our timber construction company completed the roof entirely by itself.

we are at the very beginning and don’t yet know what we will build.

Then you should best preserve this open-mindedness and not poison it with too much reading. The peaceful and factual comments read so far in this thread are not typical; much more often you will read bitter disputes among enthusiasts, X is the very best, Y well, and Z no, definitely not.

Wood regrows, stone rather less so.

Yes, I very much hope that the Laacher See volcano will remain quiet for a long time. By the way, with wood, "solid" is more eco-friendly than timber framing, as the latter uses engineered structural timber, while "solid" can be a kind of "formed ham." The current wood harvest years are unfortunately strongly affected by windthrow, and the use of "assembled" wood building materials is more eco-friendly than that of "grown" ones. Unfortunately, in my opinion, this is perverted by the wall thicknesses in the Energy Saving Ordinance, but that is another topic and a very wide field.

At the beginning of the topic, someone advised good cooperation with those who are supposed to do it.

I think that is an important tip!
All construction methods have advantages and disadvantages. Much of it is judged intuitively (which is fine), and with all methods there are mistakes that can be made.
Therefore, I would also put the emphasis on whether you find someone during your initial research whom you personally trust or come to trust, someone who is likable to you. Such a person could be a tremendous help for this decision.
He or she should of course also be reachable during the building process; otherwise, all that trust is useless.

Therefore, I would also place the focus on whether you find someone in your initial research whom you personally trust or who seems sympathetic to you.

Yes, exactly: let’s assume the "insight" is: we build with stone. Then you are not yet at the goal, but the next round continues with "stone A, stone B or stone C" (possibly with/without ETICS). Then my mantra applies again: the "second best" stone processed by the (also in terms of chemistry with the builder) "right" contractor is better than the "test winner stone" which would be a premiere for the processor or with which they at least have significantly less experience. So: first, look for the contractor - in my opinion preferably one from the region - and then see what they recommend. You can then collect second opinions here again.