I will start on the Kiera Knightly sig.
Very nice effects and has a nice wintery feel to it. Only the text could be worked on, the render blends in very well, but perhaps too much. Very good sig, and nice woman, though the render better not have been edited lol

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Onto the first Kaka one, I love this idea and have not seen something like this before. However, quite a lot of improvements could be made. Firstly, I do not like the render used and I think there could be a better one of him and it could be cut better and not feathered so much, and then his hair sharpened. I also don't like the render duplicated 3 times in the sig, and I think 2 is max. Maybe just increase the size of the render and the Gaussian blur it, and place it behind the render. Also, the text needs a lot of work on, I do not like the number at all, it takes up too much space, and should be very small. Take the two lines away and just use one Kaka, then give it a gradient overlay and place the other bits of text around it, maybe in Times New Roman.
What this signature really lacks is colour in the bg, and the best way to do this in this kind of sig, is to get two complementary colours, and then fill a gradient, making sure the fire still stands out.
I will leave the other one, as it is not as good imo, it is an overused style.
I suggest working on the other one a lot, as it has the potential to be one of your best.
Good work Trev
