would prefer to not see the enemy's: hull points, shields points, and antimatter points, as exact numbers, but rather as more of an overall percentage of each.
You should have information through sensors (modified by local ECM & ECCM) as Class of vessel (possibly even name of ship if you can read the IFF), relative current shield strength, a reasonable estimate of current damage, and estimate of AM based on last known use of function that required it. Certain abilites should also be able to be readily discerned - such as targeting assistance, since this would make the vessel a communications hub, as well as any abilities (and strength thereof) which are witnessed being used.
It would be nice (if it doesn't become a resource hog) to have the game maintain an intel file on the various capital ships that have been encountered. A previously unencountered ship might display basic info and potential abilities, but one "known" to the player (or ally) should have some confirmed info available.
I don't know if fleet 'flagships' are contemplated, but if so, their identity should become fairly obvious shortly after an encounter starts, again, due to it being a communications and control hub.