Pokemon - Love the vibrant colours and the picture used. The abstract elements behind the picture is also very cool.
Music #1 - I love the colours and the use of Miku picture for this one. The whole thing looks really harmonize and really pleasing to the eye. It fits the theme perfectly!
Digimon #2 - I really like the texture of this one and the colour used just allows it to stand out more =]
Super Smash Brothers #2 - Love the composition of this sig and the colour combination.