I gonna make some Suggestion based on my changes to the Mod on my own, and also some experience w/ both playing and modding RTS... they however not focused on Unit balance, and while I see some problems w/ that which I tried to fix on my own submod, I think its something that U can make in anway trying to get different feels for the mod

1-Constant damage vs different Armor types
This one is basically going to "gameconstants" and changing everything to 1, but there is a thing, I'm not saying to make Inf recieve 1x damage from AT-AT, what I'm saying is to make a ATST_Damage not do 1.5x damage against 2M_Armor and then do 1.1x to T2b_armor, as this adds a lot of variables that are unecessary.

What I did in my submod was to make it based on "caliber" and "armour 'size' "

2- Use a DPS and TTK calculator
This is not a change is just so one can calculate the power of a unit, and will works better if everything deals the damage that is written

3- Boost Acceleration
The way the mod is today units are extremely slow at accelerating, and that creates a problem where units will complete halt if they lose track of the unit they are attacking, or are forced by micro terrain to do so, which makes then bad at fighting, and also creates a situation where light tanks will take the same to accelerate than heavy tanks... and also units will take too much to get to full speed

What I did in my submod was to make heavy units have an Accel of 0.02, which is still slow, but they can get go after a few seconds.

4- Smaller Innacuracy against Infantry
The T2b is one of the worst unit in the mod, as it has low health, its slow bc of the acceleration, and it cannot hit either vehicles or Infantry... which means U will lose then before they deal any damage.
In this case just reduce Innacuracy from 10 to 5 or 4 (I use 4 in this case) which will make then cut infantry but not to the point where U will not have to worry, specially because of the rockets.
Also bc of this same reason Anti-INF turretes are useless, specially against shielded Infantry

5-better fire arcs for hull mounts
AAC have the ATST cannon that fires only 2.5 degrees each side which is something U would not notice because the way they fire their weapons, changing from 5 to 20 or 30 will make the unit more usefull, and that apples for other hull mounted weapons units.

6- Fire Restrictions
The worst thing that can happen is to have a Century tank charging a weaken T-4b, but before it can fire at it, a NR soldier gets close and for no reason the gunner fires an powerfull projectile to kill one person only, wasting the shot and making you lose the tank.
That would not happen if they are forced to fire only on Vehicles, structures and heroes

7- Diversify units that are similar but from different tiers.
A problem that one will see w/ the ATST vs ATPT, ww/ the AT-ST being clearly superior, or better, the T-4b vs T-3b, in which T-3b is just less costly, but still ot worth buying

What I done to T3b was to make it into a Medium tank w/ T4b being the Heavy Tank, like a T34 and KV1.