3) A better connection between the kitchen and the dining room would increase daily comfort. Any ideas?
Yes! Kitchen is no longer lived as a purely functional area it is now considered as the heart of our home. There are many options in terms of connection, ranging from improved access to merging two spaces. Implementing a sliding or folding door with wider passageway immediately improves communication. But you can go further, and suggest dynamic partitions, designed to be able to divide or merge, as desired. See some examples, both in glass and wood, in a wide variety of styles.