We need different sized trees of the one's we have already in the game. Smaller, mini trees even? I know I could just sink the trees into the ground if I wanted too, but I'm not a big fan of doing that. And I know Thememaker's toolkit exsists.
Personally, I would love to see some taller dead trees. we only have those existing short ones or the giant ones with the faces, nothing in between. A couple the size of the large birch or the smaller sycamore would be wonderful.