That's a good question! And it is not infringing any rules - we definitely want more discussions like these on the forum.
While we are waiting for other designers' input, I can talk about some good practices we have been observing at Iconfinder.
In general, even though quantity is very good to have, quality is more important. But when you have both at the same time, it is great! From taking a look at your icons, I can see that they need a little bit more work. They are ok in general, but the icon marketplace is competitive, especially for line icons, so you would need to distinguish yourself. Try to find your personal style and put that into your icons. Also, try to think of the use cases for the sets. The food set might be used on a café's website or a cooking app. In my view, food icons should look more attractive, they should make you hungry when you look at them.
Another thing is icon families. Icon sets inside the same icon family should be all drawn in the same way. I can see that you have one family called Line, but there are quite different sets in there - some of them are larger, some have square corners, others have rounded corners.
Here is a good example of a consistent icon family: https://www.iconfinder.com/families/ego-icons-black-version
And here is more info about why families are important (we wrote about it in one of the designer reports): https://blog.iconfinder.com/iconfinder-designer-report-q3-2019-ea32aecf212b#fd72. Basically, it's because customers rarely look for a single icon. They usually look for several icons that all match together nicely. This is why having large and comprehensive icon families is a good practice.
We also have this article with tips for improving your sales on Iconfinder: http://support.iconfinder.com/en/articles/18149-tips-and-tricks-for-improving-your-sales-on-iconfinder
I hope this helps. ❤️