I would like to see additional unit types beyond what is currently available. Here are my suggestions:

Knight: A unit with a higher combat rating than a soldier, but lower than a Paladin. If unit level ups are implemented, this unit would have combat buffs similar to the LH commander.

Wizard: A (mostly) non combat unit that would enhance magic and magical effects on the battlefield. Sort of like a commander for magic users.

Crossbowman:  A stronger archery unit, which could be added with a new range mechanic….

Siege unit: In SK, siege units aren’t necessary, but could be useful if cities had hit points (via an optional wall that would cost logistics points.)  The attacker would need to reduce the wall’s hit points to zero before a tactical battle could begin…and unlike Civ V cities, the walls hit points wouldn’t auto-regenerate each turn…