Hello " ". We are not supposed to introduce our own ideas of aesthetics here. Therefore, your questions should be answered independently of the impression the granite slabs have on us. To answer your question: Yes, of course there are other possibilities. Depending on which covering/type of covering you have in mind and also (this hint has already been given) whether underfloor heating exists or not. The undercuts and corners under or beside the stairs are technically demanding. All baseboards must be removed. However, this should not pose a problem, as they are usually only "spotted" glued on the back side. Usually, the wall surface does not suffer, meaning: damage to the wall plaster is limited and can be repaired and repainted. Regarding the floor surfaces: As preparation, a mechanical basic cleaning and intensive sanding of the natural stone surface is sufficient. Prime with a dispersion approved for non-absorbent substrates, and then fill the surfaces with an industrial filler to a thickness of 3mm. This initially gives you a substrate suitable for elastic coverings, as it is uniformly absorbent. With underfloor heating, the thermal resistance should not become greater than it currently is. That would mean: only a relatively thin top covering. If parquet is desired (whether glued down or as a floating construction), then it is not possible without removing the natural stone. Because the risk that the heat supply later will no longer be sufficient for adequate room heating cannot be calculated. I strongly advise against sanding, filling + pigmented sealing. You would not be happy with that in the coming years. --------------- A difficult decision, certainly.