Hope it's not too late to join the party
Love the progress on the legs since you started this project. The new toes in particular really ground the design. However, from the side, it really just seems like there needs to another toe as the ankles seems cantilevered too far towards the rear. For a different approach if the foot was made just a bit longer so that there seemed to be a naturally angled "foot-like transition" towards the toes, thereby adding a bit of extra suspension to the legs. It wouldn't be looking as much like a Tau foot as it does now but it would allow to dispense with adding a rear toe and it would allow make the model just a little bit taller too, further highlighting the "Tower of Power" idea you mentioned earlier.
The shin armour is great touch. Don't alter it anymore, in my mind that is good and done. When you look at it from the front though once thing that doesn't look quite right is the size of the shin itself. it looks downright flimsy, almost like it needs a calf muscle hydraulics box or something.
About the engine grill, while I agree that the orginal wasn't detailed enough, this fine mesh design doesn't quite do it for me. It just seems to be too much of a break from established Tau design language which is all about the horizontal lines. Have you considered trying to mimic the triangular ridge system of vehicle engine pods. Considering the new and improve size of these suits I think it's safe to say the power requirements could be mirrored by a borrowing of that design element and it tie it in quite nicely with the other elements of an army. (and yes I do realise this won't be displayed on a table for a game but people might still read it that way
)
Plain battlesuits? What are those?
Cheers,
Dark_Gear