When you make a map set, should you follow the unwritten rules of Wolfenstein? No Hitler ghosts, no Mutants mingling with regular guards (at least not on the straight maps, the bonus ones are another thing (I'm thinking E6L10 here)...) No holowall tricks, no silly stuff bouncing around, no nothing...
I avoid the "holowall" thing altogether since it looks so bad when you walk through it, but also because it causes problems if a door closes when you're in it. I'm not fond of the Guard Statue thing, either.
* Officers are allowed in episodes not used in the original game
I have no objections to this.
* All wall patches and sprites can be used all over as well
I have no reservations about episode-specific sprites being used in "wrong" episodes, but "Red w/ wreath" patches on grey walls, etc. never did it for me.
* Mutants appear as guards in remote or secret areas and secret maps - never together with the other guards (at least not in the same room)
I have no objections to the Mutants appearing on any maps, secret or otherwise.
* Hitler ghosts are allowed everywhere as well (but I won't use them heavily, but just the fact that they are there makes the whole thing more fun, in my opinion)
No objections, as long as you're given ample ammo to defeat them.
Until recently, I've always replaced brown marble #2 with something else - I haven't done so for a while. To tell you the truth, I like this shiny variation, but the two other marble textures (#1 and the one with the banner) haven't got the same hue. Do you discard this when you map, or do you use it? Same goes for gray stone #3. While it works good with gray stone #2, placing it next to gray stone #1 just kills its flow.
Same here. I avoid the Brown Marble 2 wall whenever possible, unless I want to mark one specific spot as a Pushwall.
And what I'm thinking about is this: Would you play a map set, open up Episode 1 and see officers, mutants and wall patches not used before Episode 5, 6 or something like that and feel totally let down?
I wouldn't feel that way at all; it always gave the game more variety to me.