1: Fully-statted monsters - such as presented in the sample adventure, or the Monster Pak - are useless unless you enforce the following:
A: Players must be allowed to peruse and dig through the monsters are their leisure. Ideally, you'd have a DM copy and a copy passed around between players for browsing.
B: Any time a player wants to introduce a monster, it must be something from the available monsters -- no on-the-fly stuff.
-OR-
2: Monsters (peasants, et cetera) need some kind of special rule set. I'd take a page from Shadowrun 2nd edition, and give a dice scale for monsters. Any time they want to do something, they roll their alloted dice (so maybe level 3 monsters always have 6 dice to roll for anything).
I kind of favour 2, simply because most of the abilities for statted up stuff are never used; there's simply not enough phases in a flurry to use anything but hurt-stuff attacks.
Maybe there's a 1.5 in there somewhere, with monsters/targets getting a stat template of less traits and abilities and such, but wider scope.
Michael,
I use fully-statted monsters, and replace abilities - but never, ever numbers - to match what I want. So, for example, I take the Death Knight, because I want a level 5 creature with a good offensive ability and an item-destroying ability. Let's say a player said that, hmm, an Acid Troll approached. Smite Vigorously at 6 can stay, and Undead Flesh is just renamed to Regenerating Flesh. Destroy Metal Weapons is wrong - let's replace it with Destroy Wood and Leather, which is specialized enough for a supporting ability. Animate Skeletons and Zombies is the only one that doesn't fit well, so I nix it and add something colorful like Etch Stone.
I do switch attributes around, of course. In the Death Knight -> Acid Troll conversion, though, I don't have to.
Me too, what Clinton said. Sometimes I'll juggle some numbers around, though, a die here or there.
I wouldn't be nearly as good at creating nasties on the fly in Donjon if I didn't have a passle of pre-made examples available to "mutate" and the excellent examples of ability usage given with pre-made critters.
Clinton,
That's actually what I've been doing. It just seems like it'd be better to somehow structure that into something.. I'm missing the word I'm looking for. But rather than ad-hoc it all the time (well, here's a level 5 who's pretty close..) just stat up generic-y stuff.