Several Revamped Renders

I recently went through an intense learning weekend finally learning how to properly use Cycles and how to light and compose shots better. When the weekend was over I felt that it was time to revamp a lot of my old models’ materials and renders. Here are my favorites of the new renders. You can see the rest of them, and the old renders to compare/contrast them with, on my blog.

All rendered with Cycles with 1000 samples.

I think the center chair is shiny, you should better remove the glossy material

The shark render looks somewhat flat, maybe You could add some fog to emulate the water? Also, a bump map would do a lot of good.
The second render I like, although a flatter aspect ratio would be better fit for this composition. And instead of a sharp edge on the background, a curved one might work better.
In the third picture, the symmetrical textures are really putting me of. There is also a shading issue on the chairs legs I think? Or maybe this was intentional…

The shark makes me think its a game cover for a Super Nintendo. The wine glasses themselves do not really look like glass, looks more like mirrors in the shape of wine glassed. As far as the chairs…really do not like them. I think a rework in the shading is needed. I like the model of the chairs, just not the shading in them.