As a GM I try and tailor a game to my players, just what that is at the moment is the hard part. Do they like battle, riddles, traps, physical or mental challenges? Those are the questions I need to answer when I create my game.
To me it seems from your post that you are trying to highlight one area of RM with each room to show RM's strengths and weakness to your group, I do not see very many RM weakness but some do. So I would stick with that. The area's I see that you are missing is spell casting and/or magic item use, a chase room, a sneak past or fight room, and a social gambit/challenge room. And maybe a room that seems to be something but is rather nothing but a time waster. Other than that any area in the Rules can be a room for your to highlight.
IMHO it is almost better to have fewer rooms with the option of more rooms on your part for the first timers than a lot of room that the party does not finish.
Once you have those down then you can pre-make the PC's for the group so they can just jump in a play with some simple explaining from you. IMHO you are almost designing a Tournament Dungeon with all of the things that go along with that, ie rule set, age, time limit (better under than over time), player vs PC knowledge and do players want to act or just play.
MDC