It boils down to a preference thing, but if there are two 'classes' of rooms in about equal number, I'd mark both rather than only one. If every time I look at a map, it reminds me of one case, but not the other, then at a glance mid-game I'm as likely to see "nothing happens here" as I am to remember that "nothing = HazEnv event."
Viewing post in Headless System jam comments
I can see what you mean. I'll play with it a bit, could add a little balance to the second page if every room title has a symbol on both sides.
I forgot to mention the randomized corpses in rooms, but the intention is to add some slight replayability and an extra opportunity for the monster to appear even if the players never interact with the smaller cargo room that acts something like a lair. I think corpses appearing in places that feel weird gives people more to wonder about, like why is somebody else stuffed in Conrad's cabin? Maybe the monster was hiding a body, maybe somebody got cornered frantically trying to hide, maybe the dice line up and put Conrad in there so it just makes sense. I can see how it could make for some awkward interactions though, like finding two sets of spare keys in the cabins or the first aid key sitting right next to the locked box, but I'm not sure how to remedy that without assigning every body to a room and doing away with the mix-up entirely. I guess that might just have to be left to a Warden's discretion to fudge some things for their own game, which I don't love, but I'm certainly open to ideas on changes to the topic.
Re: corpse locations: as soon as I hit post, I remembered these are people being hunted through a claustrophobic ship by a crazy monster, and they all probably have access to every room in the place. "Flee to wherever you can reach" is logically going to give you some 'illogical' hidey holes and randomly scattered items. Weird feeling is right. I don't think duplicated items is a big problem - the captain could plausibly have back-ups of any card/key, which scatters in the melee.
The replayability and sense of strange are totally sensible out-of-universe justifications too.