Wall unit with good wood quality

With €1000, you don't get far with solid wood.

- one day you realize that you don't need 99% at all -

1000€ and solid wood is tight, unless you are looking for something used

Take a look at the classified ads, maybe you'll find something you like

At some point I stopped making too many demands as an uncreative mind. Otherwise, the opposite would not be feasible

Then it’s pointless to make any suggestions here, because that would lead to boundlessness. There are so many design possibilities at different prices.
Form and color can be combined and beautiful ensembles can be put together. For me, it is very important that the furniture matches the room.

The living room walls I saw in person were always made of particle board

Then you must have looked in the wrong price segment. An ensemble made of solid wood, whereby the type of wood, the construction method, the surface treatment, the fittings used, etc., also matter, you will certainly not be able to get within the mentioned budget.
For special requests, a joinery workshop is certainly a good contact and can also provide good advice.

In summary: Don’t let yourself be fooled. Even though I have read a lot of nonsense (check out

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, that is more entertaining than most comedy shows ;) ), I can say that it is definitely not possible to get a reasonably good wall unit that cheaply.
Best regards