I imagine a typical game goes something like this:
- Player designs some units
- Plays a scenario.
- If they fail, go back to unit design and tweak / create units.
- Try again
What if while the battle is paused, the player could jump into the unit design to create and edit units on the fly? It would allow for less restarts for a given scenario. You could even explain it away in game terms as the player having sophisticated warfare analysis software and ultra just in time manufacturing. Just an idea, not sure if it is feasible or if players would find this more entertaining. It would allow a player to be more reactive.