sig 1 = 2/10 - I'd say one point each for the renders. it doesn't look that bad. however it doesn't go with the bg, you should use a different font, and you should probably add a border.
sig 2 - 1.5/10 - same as above. reason I took off .5 was cuz the right pic looks alil' blurry.
sig 3 - 1/10 - pic, font, font color, pic renders, pic quality, lines, and bg all need improvement.
sig 4 + 5 - 1/10
sig 6 - 3/10 - i love mario and luigi. juss not a fan of that bg
sig 7 - 2.5/10 - needs a different bg, a border, a different font color and/or font
sig 8 - can't see
sig 9 - 2.5/10 - a lil' plain...and if your only gonna do the motion thingy with the words i think it would look better on a less wider sig or if the text was more in the center. font looks alil' strange to me though.
sig 10 - 4/10 i like the color of this bg and i like the gif of the name. however its alil' plain.
sig 11 + 12 - 2/10 - too much empty space
sig 13 - 4.5/10 - you did a pretty good job cleaning the pic to make it a transparent gif. only problem is the font again and all the empty space.
Yeah like I said keep practicing and you'll become better at making sigs, but right now your not that good no offence, but everyone starts off like this, and then they become really good, and I am sure your goingto reach that level.