Rocky Mountain and Lake

Hi there,
I’m new to BA and have been using blender for three or two years now, and I wanted to show you the first project I’m working on by myself. Before, I was just following tutorials from or else, but now I decided to do it without help. I started this project for some hours now, and I was quite happy with those results. Here is the first one:

I did it with only 10 samples, it took three minutes to render on CPU (I know, GPU is faster but I don’t have a separate one).
Please give me any feedback, it’s the best way for me to learn.

PS: Sorry if my English is bad, it’s not my original language.

Here is another one, 300 samples, using Ray Pump. It costed 78 of my free daily render points… Anyway, I’m happy with that!

I really need help to improve, please give me feedback.

Right now it looks like the island is solid rock with trees growing out of it. This wouldn’t be realistic. You need normal dirt for vegitation. look at pictures of islands for reference. The sky can use a new texture. make sure that the horizon of the sky matches the horizon of your image. As in, the clouds show perspective towards the bottom.The ripples in the water need to be much smaller. Again look at some reference of lake islands. Also, work on the lighting some more. It looks really washed out. Try using an HDR with a Sun Lamp.

Thanks for your quick reply, I’ll try to improve. What do you mean by normal dirt ? Is it a problem with texturing ?
For the ripples in the water, I know it’s too exagerated… I actually used HDR, but I wasn’t happy with the background it gave. So I did the film transparent and added this background image with compositing, and I was wrong.
Thanks for the feedback, now I will use reference images as much as possible.