Well, with only one combat encounter per day you don't really need anything to counter the 15-minute adventure day. Heck, you could almost turn those dailies into encounter powers and not notice the difference.
Well, it's more that the dailies tend to do game-breaking stuff when they can be used every single encounter. In multi-combat sessions you can at least go, "Well, at least they won't have *incredibly destructive power X* next encounter". Not so in my campaign.