No so much familiar with most of the lists, but some comments:
Why making a new Sumerian list when there is allready one? I think it´s better to "spice" these a bit up:
I´d make these light, not heavy chariots: First of all, heavy chariots with B6 are not of much use. In nearby any case they will need to wheel a bit and have then M3. 6" charge range. Not good for a unit that must charge to be effective. Second, the illustrations in CW seem not to justify treatment as heavy chariots, they seem to have more in common with light chariots. For the less manoverability they have only M6. However, the following special rule might give some extra flavor:Medium chariots:
-1M when moving not straight ahead. Does one strenght 3 impact hit on charge.
So, you loose some movement when wheeling around but you get a single impact hit for that. A compromise between light an heavy chariot what seems a good thing to me.
I´d also drop that giddy up rule and improve characteristics to that of the other chariots warriors (T4, A2) but leave the second wound out - after all there is only one warrior on the chariot, and i see nothing to justify two wounds. Also i add a +1 armour save to the front for that front shields attached on the chariots...the chariot will need it and it´s a nice detail on most model that can be brought into play in this way.
Point costs should be unchanged. Even then i think the later available chariots are far better. You get the following after all:
Sumerian chariot...30 pts
M6, WS4, BS4, S3, T4, LP1, I4, A2, LD8
Equipment: Hand weapon, javelins, light armour, front shield (as half barding, but no movement penalty)
Special rules: medium chariot - counts as light chariot but suffers -1M (-2M if marching or charging) if moving not straight ahead. One impact hit on charge.
Next are the spearmen: I dont think that this phalanx rule has much historical sources so i´d drop it. After all, i think sumerian spearmen are quiet okay, maybe make them cheaper as the sumerians must rely more on them than the later (chariot riding) nations. Light armour should be only 1pts to make any sense compared to large shields. Also, units not armed with large shields might take pikes (+1pts) to portray these long spears often seen on pictures of Ur-style spearmen. These are not real pikes after all, but for in eriod play the same effect seems okay for me. After all, equiping the spearmen with armour and large shields for 4+ armoursave is still better.
Bowmen should keep their composite bows, i think Nigel knows what he does (most times, at least!
. Maybe gutians can be a point cheaper, i wonder why they are more expensive than in the babylonian list.
For egyptians i think it´s also better to take the existing list as a base, if i remember right guy has this already done and his lists were pretty good. Also egyptians haven´t used thrusting spears in this period, this is quoted also in CW itself
Don´t know what to write on the other lists, sorry.