Beautify my pixelart animation

I am working on a game and need a fix for my animations. They are loop animations, like walking, running, standing. These animations are not perfect, here and there pixels are missing. Sometimes shapes are not clear and so on. I don't think this is a complicated [login to view URL] just need a good eye for design and a pixel animation program like Aseprite or similar. There are also free ones. Each loop animation could have 240 frames, each frame is 64x64 pixels. Your task: - Compare the previous frame with the following one. - Correct the missing pixels. - Look where a contour is missing and add it. - The animation must not suffer from the corrections. - Make other decisions that correct the animation.