Last year I took a landscape painting class at Schoolism (I did a lot of urban landscapes in it as well) and it really helped me with getting over the fear of drawing environments. This past month I have been working a lot on my reboot of The Pines and I have found I have a lot of environments to design, both indoor and outdoor. Out of all of them, the ones with trees give me the most headache. Environments really are important if you want your images to be interesting and convincing. If this list seems overwhelming then definitely give it a shot. I promise by the end of a month you will see an improvement in your work.