Proposed changes for the fortress, additional techs and champions:
For most civs there is only one technology in the fortress to research: will to fight. On top of that, some may build their heroes there too. But with the upcoming changes and the effort to move hero recruitment to special buildings (i.e. ptol in alpha27), there should be another use for the fortress apart from its poor defensive capability. Therefore I propose a number of unique technologies that should be researchable inside the fortress:
These techs would be in a similar fashion like the ones in the imperial ministery (han). You will get to choose one from two mutually exclusive available techs: One has a more offensive character, the other one a defensive; i.e. Siege weapons deal 15% more damage or buildings have 25% more hp
Another set of possible technologies are: one that give a small buff in general or a big buff for a certain building/unit type; i.e. Group training time -5% for all military units or +2 pierce armour for slingers
Making these late game technologies mutually exclusive will add another layer of decision making and planning to the late game. Do I want to specialise in one unit type and risk being countered by the enemy? Do I focus on the defense as a flank in a TG or do I try doing an all out attack?
Additionally there should be a change to the requirements for training champions:
Some are trained in barracks others in special buildings. Take as an example the Briton Argos (swordsman) in comparison to the Maurya Visha Kanya. Both cost exactly the same, have the same training time and the same base stats. But the big difference is how you access these units:
As a Briton you just click a tech for 600 food and are able to produce your champion out of as many barracks as you like, making it cheap and easy to mass the unit.
In comparison as a Maurya you have to build a separate building costing 200 stone and 200 iron each. You have no way of effectively massing up your champions in the same way as the Briton without having to expense a small fortune.
It is normal to have 8 to 10 or even 12 barracks in the late game. Therefore to have the same production capacities as a Maurya you would have to pay between 1600 and 2400 stone and iron, being the equivalent of 2 to 3 fortresses and 20 to 30 champions worth of material (ignoring food and wood cost, as they become less important late game).
That is why I propose the implementation of one of these 3 different approaches to even out the disparity:
1. Champions can only be build in a special building like the Harmya or Syssition
2. Make all Champions be build in the fortress, with reduced base training time
3. Allow Civs to upgrade their barracks or stables for a price of 150 stone and iron.
There they may build champions at the cost of having double the training time for civil soldiers in that barrack