I think it's kind of hard to compare sketchlike black and white pictures with color. The color makes everything look more full and vibrant whereas there's alot of white space in the early ones. I don't think your characters look inconsistent, but the poses sometimes do. Occasionally there are wonky proportionings. Other times, the proportioning looks alright.
Are you searching online for poses and stuff to use as references? I'm not too hot with the whole consistency thing either, and I've found that relying too much on references makes me more of a copy machine than a learning drawer, because if there's suddenly a pose I can't find a reference to, I'm done. I've found that just drawing the same person in different poses and view points is the only way to be more consistent, and it helps to have a pose-able figure to give you the base of your pose, but not enough to just copy. Consistency comes with a core understanding of color/anatomy/everythingelse, and that understanding takes time, so don't give up. In the past, I've thought I was at a standstill, but looking back at those times, I can safely say I've improved. It was probably just an illusion from me comparing myself to people alot better than me. So rest assured, your work's not for waste
