Thanks for getting in touch!
Yes, we are planning to add more types of soldiers. For example, when we add walls and towers we will add siege units. Also, we have yet to add the most iconic and elite unit from the era. In addition, we plan to add unique units for factions, like the Egyptians using khopesh instead of sword.
When it comes to formations we are not 100% sure yet, but we will at least improve how units find a path to their destination. Right now they keep their distance to other units you command at the same time (like in Age of Empires 1), but we want them to attempt to move as a group to the same destination instead. It's a bit hard to estimate when we will have time to add this improvement.