Woah, from out of nowhere with a really nice and "far along" (well developed) image! Great to see this. I agree with the others, slightly less flat/even lighting would be good. But the biggest issue (probably the only one that *really* matters to my mind) is that foreground tree on the right. It is really just too evenly lit, flat-looking, and low-poly. It almost looks as if the bark texture is luminous, in fact, and if that's true simply correcting it might fix most of the issue. Using a higher-poly model would be ideal, but if the shading is corrected, it will be much less of a noticeable issue.