Thank you very much for your appreciated feedback. The thing you propose for the bathroom ceiling was already done two years ago but as long as people refuse to aerate the bathroom, it will occur again. So I have to first make sure that the bathroom is being aerated by itself, before doing it again.
The shelf in the kitchen is very tight, you are right. But I was rather thinking of removing it because so many pots, plates, glasses etc. were falling down...
The wash machine and dryer can be used on Wednesday mornings, but Mrs Zuber is a much more comfortable option ;-)
I will bring along an electric heater next time (even though my husband is afraid of people covering it and causing fires, so I have to install fire detectors as well). You cannot immagine how individually people are when it comes to temperature: in winter, 50% of people write to me "it is musch too hot in here" and the other half says "it's way too cold". (A floor heating needs 24 hours for being effective, so not much room for a try and error process in a week ;-)
I hope you enjoyed Zermatt and I am glad that the weather got warmer.