Help with Walking - Puppet is slouching and distorted

Hi there! New to the forum - but I've been reading everything I can find on this subject here, but so far none of the fixes have really helped me. I've also watched all of the OK Samurai tutorials on walking, and rigged my puppet as he demonstrates with the 3 view Eliza puppet. I'm still having issues with his walk. His shoulders slump down and his feet in particular are really warped. I've messed with placement on my neck, hips and waist tags with no major improvements. I have sticks in place. Desperate for a little help - if someone is willing to take a look for me. 

Also, my arms are not moving correctly - but I haven't even started to tackle that - which I figured would be easier than what's going on in general. 

Here is the puppet: https://drive.google.com/file/d/164AVcQvXXuCwp4_umLgJ6bHtEmkmKm_y/view?usp=sharing

Thank you in advance!