First of all thank you for you feedback : )
I picked now 3 of them that I think have the most potential and polished them up a little.
It's still pretty rough but I think you can see the directions the characters could go better this way.
Bottom left could be a guard protecting his land and bottom right could be some sort of cyborg monk living in his temple.
I'm not sure what could be the background story for top right, however I think that I like her the most because I feel like going with a light-hearted joyful look, which will be much easier with that character. Time will tell, what I will pick in the end.
All these characters are probably not what they will look like in the end as I want to experiment yet and try out a bunch of stuff.