If you are going to be putting any of this on a demo reel, I recommend dropping the chess board. There is a strong chance that your tape will be ejected the second anyone sees a chess board...no matter how good it is.
Some of your images show a good sense of color. I especially like some of the elements in your "Grip Reality" images. Although I don't think the text of the title works well being integrated into the image. I actually like the cropped (thumbnail) version better. I think you might want to work on the composition a little. Just cropping a different portion of the image might be enough.
Your office images, especially the computer Monitors seem a little flat. Since you have Soft, you could easily make the monitors a little covex by assigning a skeleton with global skin, bending it and copying the model to keep the shape. There are many other ways to do this, but this is an easy way to do it.
I personaly don't think you should ever list your production times to imply you did not spend a lot of time on a project. People tend to judge your work more harshly. If don't think the work is as good as you could do, then spend some more time on it.
Not much else to say, but keep plugging away at it. Perhaps you might want to look at the subject matter others have in their porfolio to give you some ideas to try.