If you're wondering why this haven't received any feedback, I think part of the reason is because this is very nice work. I didn't comment initially because I'm not really at this skill level with sprites, so I figured I'd pass the buck. Having said that...
- I think the male character's head could be moved one pixel to the right. Right now, it doesn't look aligned with his body, in my eyes.
- I'm sure you could take this to the cluster threads and get some valuable input there. A few people are experimenting with eliminating all individual pixels, and you have a few of them.
- I don't think like the female character's top / shirt reads very well. It's the vertical red line going down her top that creates a bit of noise, and you end up with some somewhat isolated, bright pixels.
- The female character's upper left arm looks a bit big, perhaps, compared to her other arm, and the male character's arms.
Hope this helps.