Some suggestions:
Battle
F6 is good, but it's still disappointing when you want to command the army yourself. I suggest something like the one in Freeman Guerilla Warfare.
Range weapons are way too powerful. Low tier archers should be much less accurate. Bows are powerful but difficult. A beginner cannot hit anything except his own arm with a bow. Also the maximum range for firing should be at most 150m. Nowadays my top-tier archers will aim at the sky in the beginning of battle.
Accuracy of thrown weapons should be lowered, especially for AI. I actually think there should be an additional penalty for ai because one of the main difficulties in aiming thrown weapons is the trajectory. Players have to guess the range and trajectory on their own, whereas AI could calculate the trajectories accurately. Therefore AI could hit the target with a elegant curve at a long range but players cannot. It is only fair to implement an additional penalty for ai.
Accuracy for melee cavalry should be increased. Now its hard for them to hit anything on horse back, so that heavy cavalry could loose the battle against equal amount of archers.
Siege
Many of the cities and castles could be defined as "strategical point", i.e., large hostile armies cannot pass its surrendering without first besieging the settlement first (more or less like in EU4). That is what castles are for, aren't they? For example, Myzea should control the mountain pass so that enemies cannot pass from samatha to melion or orthra.
In siege there should be an opinion to build trebuchet in the reserve instead of build it in the front line and move it to reserve.
Battering rams should have some protection on the side, or at least player should have the opinion to build such rams at higher cost. Also, player should have the choice to build a better siege tower with an additional floor for archers.
The defender should be able to surrender. Also, if someone in the city is at high relation with the attacker, they could open the gate for the besieger (whereas the defender might also use it as a trap)
Clan
Clan leader should be able to give command to the clan parties. The emperor should be able to give order to all the armies in his empire. Also, they could ask the clan members to refuse to join other armies.
Fertility is too high. My wife gave birth to five kids successively in four years then die at child birth.