After the last session, I took some time to re-stock a good portion of the dungeon, and redeployed those temple Acolytes that remained. I like that this makes the dungeon feel like a dynamic place.
Shortly, after entering the dungeon the party abandoned their plans to instead investigate signs of changes to the dungeon in areas they've already explored. Near disaster, followed on the heels of that decision - in the form of wandering monsters!
I will be the first to admit that I do a lousy job of tracking resources such as torches, etc. That leaves wandering monsters as the primary provider of tension to making decisions that take in-game time.
"Do we search the whole room for secret doors, just part, or not at all?" The only reason to choose not to search the whole room is the number of wandering monster checks. The threat of wandering monsters means the party will usually look at their map, to figure out likely spots for a secret door and only search there.
To be sure the wandering monsters provides the necessary tension to those decisions, I do not make Reaction Rolls for wandering monsters. They always attack. There always has to be the threat that the wandering monster will consume resources (hit points, spells, etc).
However, I do use morale checks for them as morale provides tactical decision making - the party can take actions that trigger morale checks.
So following the wandering monster check coming up with a "1", the party was trapped in a dead-end room by three large, hairy ape-things with jaundiced, watery-eyes, and slavering tusks, armed with long, heavy spears. A fierce battle ensued and before the three creatures were killed (having passed both morale checks), two of the PCs lay dead on the floor.
Going into the next session the party is deciding if they ask Lassering Thay, the High Priest of Hades, to raise the PCs from the dead (insert evil laugh here).