Everybody has their own likes and dislikes, their own "style" in art. In 3D, to get a render looking good, it's usually best to do some postwork in a 2D application like Photoshop or Paint Shop Pro, to liven the image up and fix errors. I've wrote several tutorials before on those subjects :)

Now, here's how I made my "Wyvern's Castle" render really pop out, made "Intense"!
There is NO one perfect method for doing this stuff, each image, due to its style, and your needs will require varied treatment in postwork to get it to have "vavaVOOM!", but this set of steps worked for this image. Give it a try, come up with your own variations ;)

STEP #1

To begin with, I always duplciate the background layer, never ever work with the only copy of the original...! The save it with a new name, like "My_image_work1".

Now, I want to make the colours SLAM viewers right in the kisser! To do this I add an Adjustment Layer and increase "Vibrance". For those who don't have Photoshop CS4, use Saturation or similar controls. Vibrance is the best though.

The reason to use an adjustment layer, rather than just do it straight onto the image layer, is that adjustment layers can be changed at willl, and also, so later on, you can see exactly what you have done to the image. It's a good idea to name each layer with the effects you have applied, so you can reverse engineer it later on if need.

ORIGINAL

ADDED VIBRANCE