House from the 1950s

Hello, we have a house from the 1950s. The plot is very nice, so moving is not an option for us. According to the architect and builder, the house is still structurally sound. What bothers us about the house is the layout of the rooms. Furthermore, it could be a bit larger and we actually need space for my mother as a second residence. In an emergency, a room with a bathroom for her would suffice. According to the architect, the renovation to bring the house up to the latest energy standards would cost about 130 TEUR. The basement needs to be made dry (we currently have the problem of too high groundwater level), but even after the renovation it would not be usable as a living basement. Has anyone had experience with a house like this? Would a demolition and subsequent new build be better? (we have also already considered this). I would be very grateful for suggestions.