I wote too for battle simulator. It can be perfect tool for testing a players tactics skills/tactics scripts. Also can be good not play random battle but "selected" battle, or even "created battle" by a few parametres.
No experience is earned for any existing ships/crews so nothing in gameplay is effected.
No other player's technology level is used.
Why not - it will be better when I can play my tactics againts (selected) simulated players ship/fleet. Designs are known or this option can be affected by Espionage - better know your enemy, better prepare your tactics.
So as a implication of this it will be better to have a fleet tactics for this situation (strong enemy, small enemy) and for this and that enemy (I can prepare a scrips for battle against this Race and another against someone else).
Tactics scripts can be even be "created" via this combat simulator by pressing "create tactic" button (and than be little modified with some else tool).