It might be interesting, and historical, to allow in some circumstances the "barbarians" to raid across the red scenario border and retreat, where the Romans can't pursue. The Roman would need to fortify and garrison camps and cities, rather than just conquering the raiders' cities.

Also, you could allow the Belgica to randomly spawn a skirmisher from the swamp, and the Germans from the forest, or Helvetii from the mountains. I would imagine most of the population was rural, and you would deal with occasional raiders even if you controlled the cities. The spawn rate might be a function of faction hostility, or morale in the nearest city, or how much impassable terrain they have as spawning grounds.

Please consider a unit skill that increases marching speed, possibly at the expense of food supplies.

Please consider a unit skill that allows a unit a chance to disengage from combat.

Please consider a unit skill that lowers enemy unit morale (a unit's bloody reputation frightens its enemies).

Perhaps the cavalry should not be allowed to construct.

Another suggestion--in the later scenarios, I first completed them with attrition--just grinding the enemy down to nothing, capturing every city, resource center, and camp. Later, I tried to complete them with more of a maneuver style, capturing only what I needed to move to the next objective and leaving everything else intact.

Please consider some kind of achievement or timer to reward how quickly the scenario is completed. It will add drama when there's a reward, not just a risk, for bypassing enemies and charging toward the main objective.

I know that unit grouping is one of the still unfinished parts of Rome Hegemony. As for a finished group feature I would like to see a couple of combined arms group formations. Currently in Rome as well as in Hegemony Gold I find it very tedious to try to arrange and order a mixed group. Anything that could be done to refine keeping battleline infantry upfront and center and units like slingers to the back or flanks of a group would make issuing army moves much easier.

After finishing Chapter 1 I could think of one gameplay tweak that might be nice to change.

During the last battle with the Suebi you are faced with their approaching army separated into 2 groups the cavalry charge followed by their infantry. Well, just before that charge you encounter the city of Magetoria and kill any troops standing outside of it then the main army is triggered.

When that happened I moved all of my forces East to meet the main Suebi army in the field. When I did this I left the Suebi held city behind with 3 or 4 units still garrisoned inside. It would be an added challenge if it were scripted or the AI knew to back up it's main attacking force with any remaining nearby troops like the ones still in the city.

I won pretty swiftly against the Suebi charge, but it would have thrown a wrench in my plans if those garrison units had attacked from behind my lines. Just a suggestion, hope people like the idea.