We need hybrid and improved experience and stats system.
economy stats, if this experience or stats are increased the unit is bad as fighter.
military stats / experience, like current bad villager if they have higher level of experience.
in some way like the RPG game, you can't mastery all stats.
Other solution is have more variety of roles, like DE.
female villager
slaves---( this concept can be improved)
peasants ( villagers) that can defends with a knife or a club. Suits for some cultures.
militia :very mediocre military unit, like a policeman or patroller even a watchman, many of citizen units can kill him. ( similar to militia vs villagers in AOK)
citizen soldier:basic , advanced, elite, like actual but may be switch mode, like was suggested by another users in this forum.
profesional soldier = champion
Champion= a semi Hero that serves to Hero to defend him, an elite version of champion. Basically a promoted champion. ( similar to EE2 Art of Supremacy)
Hero=Heroes.