My humble suggestions after playing DA for a while.
The screen for invasions might best be a movie that has exciting and chaotic battle scenes with no attempt to relate to actual troops of the player and AI facing each other. The invasion scenes in DA look like the French against the Prussians in the 19th Century because of the attempt to depict the actual troops.
Just have a movie that moves from venue to venue of starwars level troops, vehicles and ships blasting each other amid fire and smoke, on or over water, in fjords and moutain passes, starwars helicopters disembarking troops and getting hit...bridges, dams, huge buildings being taken out with missiles, all chaotic dark fiery movies. No ID of friend or
foe...just heroic battle scenes...small numbers of special forces galactic troops taking a strong point or strategic starport, blowing up a gigantic dam, bringing down a giant bridge, cities going down in fiery hell....
Below all this can be the bar graph showing the progress of the battle, not in numbers of troops but just in shrinking bars in the civilizations' colors to show who is winning.