I think the 3rd one is your best from that group, but I still think it's too dark. You definitely have a dark style, which I don't like too much, haha.

Your other sigs are either over-contrasted or too dark, and number 2?.. Has some nice effects but it doesn't have a focal point, too many distracting bits in there.

Well anyway look through some tutorials on the net. Keep your style, but just improve in it.