Ok firstly the red signature; the render is fine but it looks pixelated, if it came like that then you can't really do anything about it but if you sharpened it i suggest erasing or lowering the opacity around the hair on her forehead, it distracts me xD. I can see your getting better at the blending of the render :3 but don't forget to put a border on the sig and if you did im sorry ^^;; Nice choice of colours for the second one, goes well with the render. The first one is my more favourite one though, i really like the colour composition.. pleases the eye. Also try to be more creative with your text, try looking for a custom font website/and use cutom fonts, add more text to distinguish the render for example etc etc. Hope that helped <3