I really like your second picture. It's an unusual perspective, not the classic "tourist perspective" of the first picture. The focal length compresses the inner city buildings in an interesting way.
Maybe it is the exposure or it is the focus, but something about the cathedral in picture 1 doesn't look pleasing to me. If I remember correctly, the yellow lights on the bridge are rather subdued, whereas the white lighting of the cathedral is very intense and harsh. That is certainly a very challenging lighting to catch on sensor.
and the second from the round tower beside the Hyatt through a Makrolon window, there is a beautiful view, but you have a lot of light pollution from flashing mobiles and reflections in the window
As a side remark, that round tower almost led to Cologne loosing its UNESCO world heritage title - Historically no building near the cathedral was permitted to exceed a certain number of floors thereby not restricting the view to the cathedral. That round tower was a very close shot to that title. If I remember correctly execution of the tower fell short of the original plan by a certain number of floors - a classical compromise.
