This looks really great. However you should add subcategories option.
Yeah that's something a lot of people have requested but it's one of those updates I've been trying to avoid because it'll probably be fairly difficult to do. I will add that feature in one of the upcoming releases though.
That will be nice and you should make a better version of of this script with user registration system, credit system and ability to sell physical stuff.
There are many scripts that does that like opencart etc but they have too many functions or they are not so simple and user friendly.