So I've got 100 rooms to key for the dungeon. Following the distribution in the back of the Moldvay Basic rules, that breaks out as follows:
1/6 monster w/ treasure = 16-17 rooms
1/6 monster, no treasure = 16-17 rooms
1/18 trap with treasure = 5-6 rooms
1/9 trap, no treasure = 11 rooms
1/6 special = 16-17 rooms
1/18 unguarded treasure = 5-6 rooms
5/18 empty = 28 rooms
That's 17 traps, and 17 specials. That's where all the real work lies. Sticking a bunch of monsters in a room is easy, it's the creative bits with traps and specials that's hard.
To help with that, I'm going to theme the level and use that to guide what's going to populate the "special" rooms. For the traps, I'll be hitting the Dungeon Alphabet up for some ideas, and try to be creative. I'll also try to make it a bit obvious where there are traps, so the players will have no one to blame but themselves when they fall into one. Or when one falls onto them.
The theme will be "horror and suspense." The gatehouse was definitely robot-gonzo, so I'll change up the mood a bit with the players being stalked through the dungeons by psychotic flesh-hungry freaks. Screechmen, morlocks, and goblins, oh my.
The "specials" will largely be areas where the players can pick up some hints as to what this place is, and how deep it goes. There are some big unsolved mysteries here, the first of which is why has the place been closed up for 3,000 years. I don't know, of course, but I'll pose the question via some in-game event, and see what the players start coming up with. And then I'll see how I can use their theories against them. I mean, I'll see how I can use their theories to construct an enjoyable shared gaming experience. That kills them.
Oh yeah, the goblins... more on those tomorrow. Or maybe the day after. I'm keeping the stats but badly mangling the monster behind them. You'll just have to wait and see.