Would recommend rendering out the avatar in blender, then using the rendered image.
This is for better shading and such.
The other logos look excellent.
Your logo is nice but could be easily improved, its a good start however as other people have stated the logo would look much cooler if you used a program such as blender to get a render of the avatar, and then used nicer higher quality effects as a background in the background, simple changes can make it much nicer and higher quality.
Hope this helps, good luck with your future graphics and feel free to message me on devforum if you would like some extra feedback