As jc said - materials on your rubber boat, bobber, and decking need more work - wear and tear. I would also work on the row boat, shed, and two signs at the end of the dock (and the planking on the upper sign too which is grey and grainy like an old plank, but doesn't have any cracks). Anything that spends some time in the water (or very near it) and sun shows quite a bit of wear and tear.

Personally, I don't have any problems with hard shadows on a sunny day, but it's a matter of taste and sometimes I'll soften them because I think they look better.

The logs also would never be so perfectly round, and could use some cracks running up and down and moss and algae near the water. Your log ends look great, just need to rotate them as mentioned by jc and add a little moss/algae at the waterline.

Your one hill on the left side has too smooth a silhouette among the trees

Other than that up your render quality and you'll be close

I like your scene : )  Hope you'll show us how it turns out