Your logo is like guys above said, too busy.
Try not using pattern overlay effect.
Play with shapes, try to edit them.
Try to use an interesting font. Font editing can be also pretty nice idea
Try to put N in the O letter, maybe merge them somehow.
And finally siggy
I really like it, just get rid of 'signature' text, it does not match here.
By the way, that's what I mean by saying try to put N in the O letter