With version 1.5.0 I felt I reached a point where I could start to limit some of the features of the plugin to create a free version of it. In the beginning, I didn't really know what kind of limitations I could do that doesn't hurt the core functionality, that's why I wanted to add more features before launching the free version.
Probably doing it the other way (first the free version, and then the pro) would work as well, but I wanted to know if anyone would pay for something like this. After I knew that, I was happy to keep working on my idea.
Compared by features, the free version is identical to the first version of the plugin, and all the "extra" features I added to the plugin after the initial launch became part of the pro version. This way I could keep the core functionality, without annoying limitations and I can provide additional value with the pro version as well.
By making a free version of the plugin I had to update the landing page as well.
I already changed a few things on it after the launch, and I wanted to keep most of that but I ended up re-building almost the whole thing :D
I've created a "How to" section where people can learn more about the features of the free and the pro version as well. I felt that a simple feature list isn't enough to represent all the capabilities of the plugin.
Regarding the free version, my first idea was to submit it to the WordPress plugin directory but after I learned more about their requirements, I realized that it would take much more time to make the necessary changes than I could spend on it.
I'll rewrite the whole plugin for v2, and while doing that, I can meet all the necessary requirements as well.