Your case is made from modern surface textured and coloured Leather not not Vege tanned leather also it is rather a light colour. One of the most problematical Leathers to remove scuffs and marks from also if you apply any oil based preparations all the places that have had the top coloured finish Leather removed revealing the leather fibres below will darken and stand out. So to cover blemishes in this type of leather will need a little more effort than rubbing on some wonder potion.
Looking at the photographs I feel that it may be the corners that are bothering you, from what I can see the finish has gone and the Leather fibbers are showing, and to fix this you must start by removing the fibbers that are sticking out by cutting them off then smoothing the area with some very fine abrasive paper making the leather smooth again. Now you must repeat the first part of the first treatment that was originally given to the Leather before the colour was applied so you will need to obtain what is in the photograph. It does not have to be that make and for small areas I have found Acrylic varnish will work as a sealer.

[Linked Image from i.imgur.com]

You apply this to the damaged Leather surface this will seal the leather to allow you to apply some Acrylic colour matching the rest of the case then polish the case with some clear wax finish. Though a good finishing treatment for light Leather is a mixture of white Bees Wax and Petroleum Jelly. Looking at the stitching it does not look like the traditional Linen thread it could be man made or cotton so rubbing a little Petroleum Jelly into it would be a benefit.
I ask is it worth the effort.