I pretty like it. The last one is porbably the best. You always use very strong colors, get them a little down. This is why the last one is my favorite. As well as the colors the bg seems very much the same at some parts, it is always the same scheme. At the first mario, I like the effect left of his leg. That looks pretty cool. You have to work a little bit on depth, some more on your color and lighting. Good luck. And remember to only use one spot for the text if you are not sure where to put it, the one down would be enough.
