It would be most helpful if the tactics settings we use in each match were displayed in the Post-Match Summary page next to their efficiency rating. As far as I know, there's nowhere to view one's past tactics settings once they've been changed. Of course, I don't mean the opponent's tactics, buy my players'. Late in the season, it would be helpful to have a reminder of how effective my tactics were the first time I played a team so I don't make the same mistake twice.
If such a feature were in GKO, it would also open the door to an option to "send scout" to a match that is not my own. I could keep an eye on my rivals this way, to help guide my decisions on lineup and tactics when we play each other. The scout would make their best estimation of the two teams' tactics, with the level of uncertainty related to the level of the scout, like it is for players. Also like for players, energy would be required for such an action, and 50 energy seems fair, IMHO. Also, scouts should only be able to be sent for this purpose to immediate league or cup matches. No getting to "send scout" to matches weeks away with energy now.