Another important factor to be considered is how the case was made. The leather case should be properly made with precise craft, measure, and seal. Stitched cases are better than glued ones since they are able to withstand use over time. Also, check the leather if there are no cracks in the material.
Convenience is the last but not the least factor. A good case should have easy access to all the functions of the device like ports and buttons. You wouldn’t want to always remove the case if you want to charge your phone or use ports for earphones. Also, there are people these days who do not want to carry a lot of things when going out so if you are one of them, you may try those cases with has a free card holder inside.