Thanks for the reply, I don't have much time to type since I have work soon but about the foot,
The front "toe" and the back "heel" can be pivoted up and down while the center wheel is allowed to descend, there's also a small wheel on the front (might add one on the back heel as well) toe that can descend to act as a stabilizer. The heel can be gradually lowered to act like a inline skate brake. Also, the black tips of the heel and toe are made of hardened rubber which can be replaced.
The foot doesn't allow for torsional movement since there is no ankle but since the point of contact from the toe and the heel is like that of a bicycle, it stays upright on it's own by utilizing the same principle. Only problem is that the legs can't stay too close to each other (which is what ironically happens in this pose).
I'm aware of the popular placement of wheels on the back of the foot but for me that only causes the possibility of the entire mech flipping forwards unless there are wheels embedded on the underside of the foot.
I know the chest and lower abdomen conflict with each other and the rest of the armour itself but it might be too late for the changes. The "ribs" are slats of reactive armour placed at where the lower abdomen would tilt from side to side.
Thanks for the comment about the calf though, no one ever said anything about that and it's not something too late to change since it's just a bucketfilled outline atm.