Pulkit:
I may have mentioned before, but you have a chance to do something really unique with this mod as far as unit design and balance goes.
I'll expand on this a bit. A lot of this is from Warcraft and Starcraft and Command and Conquer style games which are very different from AOE2 ( and I don't mean graphics or theme ). Infact as far as RTS games go only Rise of Nations is in the same pattern as the age series.
Let's consider faction/race design for the moment. In WC/SC/CnC/etc, all races are fundamentally different to their very core. In AOE2, all races are basically the same. The only thing different about them is the unique unit and civ specific bonuses, and late game ( ie imperial ) there are some upgrades only certain civs can get.
Unit design is again a big difference. In Aoe2, an un upgraded militia is virtually worthless. Not so the case in other games, where tier 1 units often form the bulk of their army even in the late game, with a few supporting units as 'high tech options'.
TOME meets this half way on both counts. All the civs have their common units, but they also have a whole host of different units, and there are a lot of expensive techs.
IMO there's a lot of scope for improvement, keeping the following in mind
faction design:
1. A faction's unique units or techs should be useful, and should not be overshadowed by the standard units.
2. A faction should have some uniqueness or flavor to it. In AOK, a large part of it was accomplished by civ specific bonuses. Rivendell has a big problem in this regard. There's nothing unique about this civ except the UU ( currently ).
3. The faction should have a weakness
unit design:
1. The unit should be useful, in terms of cost effectiveness and when it is available in the game
2. The unit should not overlap in it's role with another unit of the similar nature
3. The unit should have a weakness.
Some comments about current state of the game and suggestions ( as an example )
faction: Dol Guldur
-The stable currently has no real use for this civ, so why not train trolls from it instead of castle?
-Dol Guldur is quite unique as it is
-It does not have any special anti infantry attacker. This can be a weakness.
-overall DG is a well designed faction
unit: Dwarf lords ( eregion )
-Both of them overlap with each other's role, and that of the infantry UU, and swordthains
-They're really slow
-They are too expensive for the feudal age
-overall badly designed
Suggestions:
-I like the idea of having a high tech option in the game as opposed to masses of spam units. So I suggest keeping them in the game in the feudal age castle, and lower the tech cost a bit, but not by much ( say 600/500 )
-In order to compensate, the units have to be really good to justify getting them in feudal. I suggest buffing their armor and health, so even castle age units with an upgrade advantage will still only be even with them
-In castle age give them a speed upgrade ( or some other indirect buff rather than a straight upgraded unit )
-Make one of them anti infantry and the other anti cavalry, so you don't have both units basically doing the same thing. Or make one a ranged unit.