The Lindner is not a luxury hotel but is very functional and extremely well positioned. In around a day and a half I was able comfortably to visit the cathedral, the river, the chocolate museum and the major shopping area, primarily by walking.
I didn't use the hotel's restaurant but the menu looked good and had I stayed longer, most likely would have. I visited during cold weather and the heating in the room was very efficient.
As with many european hotels, TV channels were not for English speakers, unless all you wish to view are news channels. This means that those with kids or solo travellers would be advised to take some pre-downloaded movies etc on a tablet. or some such. Or make sure you have a VPN so you can view your normal domestic channels.
The staff were super, very accomodating and easy to talk with.