Keep in mind that I'm not a big module hound and never have been, so I may just be displaying my ignorance here. I haven't looked over a lot of pre-packaged DCs, but the few I have, the problem I always had with them is that there seems to be very little overall theme.
Consider that someone, somewhere, put a lot of labor and a lot of money into the construction of whatever structure now comprises the "dungeon". It's a safe bet that they did not do all that for the sake of entertaining a party of adventurers a couple hundred years after they die. All those traps, yes, they were designed with the idea of making your (the unauthorized entrant and looter) life terminally interesting. But they were NOT supposed to kill off the owner of the place, his guests, his servants or his pets, just because they suffered a failure of attention span. Those who lived and worked in a given area should have been perfectly safe just by virtue of knowing those traps existed. They should be able to go down a trapped hallway at a dead run, in darkness, wounded and panicking. You, following behind them 10 seconds later, should be in danger of your life every step of the way.
I feel like an intelligent explorer, looking over a structure, should possibly be able to figure out who built it and for what purpose. That knowledge alone should make him safe from half or more of the traps and hazards of the structure itself. A little cautious exploration, finding out the mindset and priorities of the designers, should give you enough information that most of the precautions necessary to avoid traps and such should be obvious. In short, traps that are still functional, integrated into the design logic of a structure back when *it* was still functional, should mostly only bite the unthinking and the unobservant. The real danger from traps should come from those that are now malfunctioning, and thus still bite when they are supposed to be disarmed, or no longer doing what they were designed to do.
Monsters? Same thing. If there isn't anything for it to eat where it is, it shouldn't still be there. A Ranger or Animist should be able to look at the environment in which a ruin is set, and should be able to predict with fair accuracy what creatures will be found where. A dragon living in the shell of the old keep, ranging 50 to 100 miles a day to find the tons of food it requires every week, should have long ago eaten the hill giants living in the gatehouse.
As noted above, I haven't looked over a lot of modules, and it has been many years since I looked over a DC module at all. Perhaps that tendency has changed. I certainly hope so.
For the *other* kind of dungeon, the kind in which skill in Civil Engineering, or Region Lore (north temperate alpine, local fauna), or Architecture (security systems) would actually be as or more useful than the ability to remain standing after everything within half a mile has shown up to pound on your head..... yeah, for that kind of "dungeon", I think RM is good.
