i would personally make the listings more clear like the thumbnail as it isnt clear , it just looks cheap with a red banner saying "preview now before buying" , well the mockups are the preview :) , also you need more than one mockup photo because , i would rather buy from a shop with more than 1 mockup showing how it looks in different places rather than 5 size guides , this is what i would personally do and also look on pushing more listings consistently , i do 30 a day personally just as ive automated it mostly