I believe your second variation looks the best of the three, although if you are going for a NES styled game, i'd say that the third one is better. The first doesn't look like he has a front arm on first look, and also looks like he is leaning backwards for some reason.
For the sprite sheet, cell 1x4, is that a climbing sprite or just a hanging sprite? It would be cool to see the character climbing walls in some way, although that is up to you and how you want the play style to be.