A ceramic tiled floor, heating and dehumidification have worked well in the garage for me for nearly 20 years. Walls are white painted plaster with strip lights at shoulder height, to throw a bit more light under the cars. Electric roller shutter doors are very satisfactory too.
A few framed pictures just make the place a little less austere looking.
Flowers? Vases? Curtains?
The one thing I have often wanted in the garage is a urinal. How often do you get started on a job only to feel the need?
