Not for Crusade, but this idea could maybe be on the menu.
There've been quite a few requests for a Battle Arena type of Battle Viewer to go along with the Ship Designer off the main menu. Personally I don't really care about this, but it's crossed my mind that a "Battle Simulator" (in addition to the requested from the main menu) work its way into the main game.
The way I would envision this would be that a player could attempt to simulate mock battles from within the Ship Designer in-game with what's know about enemy fleets. For example, what's known about a specific enemy fleet, derived from espionage, sensor tech, and your captains proximity to enemy fleets in space - could be used by a player to construct mock enemy fleets they are likely to run into and then run ship/fleet design/combinations in-game in order to decide on build-paths for their own counter-fleets..
This is realistic in that military simulations are run all of the time in the real world to determine strategy, and also offers some more interesting avenues for tying choice-paths into specific outcomes (espionage, specific technologies that allow for this, specific structures/projects etc that enhance this, and citizen involvement - hell it could even cost research points to run the sims..)..
I know that one could argue that a player should be doing this anyway in his/her head when designing ships - but this may be a more interactive and interesting way of adding a battle-simulator to the game, so that it's not just some bolt-on in the start menu, rather it's a game function that one can access from the start menu if someone's board and just wants to muck around an see ships fight.
Seems like kind of a cool feature, thoughts?