At this size there is plenty of space to play with the shape of the crown (why should it be symmetric?), as well as the shape of the trunk. Trunks tilt and twist, they have remnants of old branches. The scale you're working with is big enough to show that sort of thing.
Tree crowns are usually not one blob either, but instead multiple blobs in various positions.
This example has very exaggerated, clear spheres that make up the crown (note they're not arranged symmetrically).
These examples feel more tree-like because the clusters vary in size and are not as clearly separated. These examples are at a higher res than yours, but because these clusters are a large-scale feature, it's actually easier to get them looking good at your scale than it is to get decent-looking leaves.
I think this latest leaf texture is a big step in the right direction! The colours are alright except from that weird warm dark green at the bottom, I think the main problem is that the shape is so artificial and symmetrical, it doesn't correspond to the nice texture at all.