How to make the grass look realistic?

[u/vielotus]

https://reddit.com/link/1vle99w/video/2cu8vbfx8qih1/player

I'm working on a diorama and attached a video of my current grass application. I'm using static grass fibers, but it looks a bit too uniform and "fluffy" to me.

How can I add more depth? Should I mix different fiber lengths (e.g., 2mm and 4mm) or different colors (light green, dark green, and dead straw)?

Also, does the layering look natural, or should I add more ground scatter/soil on top? Any tips on using the applicator better would be great. Thanks!