Another approach to Solitaire, for the module developer to consider, is to not have a special “God” role but instead rely on the player to switch sides.
Since 2020, Vassal retire/side-switching offers a sensible default that works especially well for 2 player games. Combined with a hotkey or easily accessed button, this can be efficient for the solo player and secure for opposed games.
For modules with side-specific features this technique helps make things consistent for the solo player.