First Terrarium, Need Help!

Here are my first terrariums!. I'm very excited, but I'm not sure if I did it right at all. I have a layer of rock, a layer of charcoal, and then soil/plants. Are they too close together?

I also want to start a new, enclosed terrarium that has plants that I like more. I want to have more deciduous plants like ferns and moss in an enclosed terrarium. How can I get started on one of those?

Edit- The last ones were leftover plants that I planted in phillies ice cream hats! Not terrariums but they live next to them so I threw them in.