After going non-exclusive on ThemeForest, I created the Ghost Themes Bundle which contains 8 of Ghost themes. Going non-exclusive means that ThemeForest will take a big amount of commission for every sale I do there, also this will apply to my account as I can't select which products to be exclusive and others to be none-exclusive but I hope that selling themes on my website will make a balance between the two. One of the advantages of selling on my website using Gumroad is that I can provide different packages, discount codes and know my customers well.
https://aspirethemes.com/bundle
Update: Added to Product Hunt https://www.producthunt.com/posts/ghost-cms-themes-bundle