There is a whole subforum here on pen photography which is a great place to start reading up on how to take better pictures. You mentioned you take pictures at 3 different angles....that's all good and well but it you're only taking on picture of each angle, it's not going to turn out that great.
I would say to start you need to build yourself a simple photo tent (pvc pipe and plastic sheathing with a couple of lights will do it). Take many, MANY pictures by doing what's called 'bracketing', which is where you take several pictures, change the aperature slightly, take several more, adjust it more, take several more, and so on. I use basically the same background on every one of my pens but the pictures can look way different even with the same settings because of the color of the wood or amount of light that shines off the hardware. There are many factors to taking a really great picture.
The simplest thing you can do though, is to get yourself some simple photo editing software. Photoshop would OBVIOUSLY be the best but is expensive....a cheaper option is something like Microsoft Digital Image. It won't fix a shaky hand, but it will have adjustments for light and color balance, have contrast adjustments, give you the ability to crop, frame, overlay text, etc. For less than half the price of one of the pen kits you're showing us here, you can take really good pictures (assuming you have a decent camera to start!).