So I just learned there's an option to automatically hide spacesuit equipment in settlements and other breathable atmosphere environments. Just gotta go into the equip menu for helmet & spacesuit, and enable it via key press. Or R1, in my case.
Yeah, it's nice for some player immersion. Sadly the game still reads it as the spacesuit and helmet being worn, which works for stats, but does lead to random NPCs talking about your spacesuit/helmet and boost pack while you're allegedly not wearing them.
Pedantically, there are two separate checks being made: the spacesuit is made invisible if you're in a "settlement" area (eg New Atlantis, Cydonia, Akila City, Gagarin, The Clinic, The Den), and the helmet is made invisible if you're in a "breathable atmosphere" area. At the moment, all "settlement" areas are tagged as "breathable atmosphere", so there is no situation where you'll be wearing the helmet but not the spacesuit.
However, not all "breathable atmosphere" areas are "settlements", like your ship or the random outposts you might find while exploring. In those cases, you'll be wearing the spacesuit but not the helmet.
This becomes relevant due to companions, who appear to have only
one check, for "breathable atmosphere", which renders their spacesuit
and helmet as a set invisible. So on your ship, your companions are in their civvies, while you're still in your spacesuit, albeit helmet-less.
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A couple of things I learned about wildlife fauna on planets:
First, there is actually a rudimentary ecosystem on planets, which might help if you're missing fauna scans. Predators will hunt prey animals, so either follow predators when they're rushing across the landscape, or hang around prey animals until the predators arrive. This might take a while, so it's your choice whether to wait or look for more by yourself.
After the predators descend upon the prey animals and kill them (or get killed) and things settle down, wait a bit more, and the scavenger animals will arrive.
Second, completely unrelated to the first, is how some categories of fauna, mostly scavenger types, are considered non-hostile. Meaning they won't react to your presence, and if you circle around to their rear and crouch, you'll be considered "in stealth", even if they detected you earlier and would otherwise detect you if they were remotely hostile. In effect, you're "stealthed" because the critter simply doesn't care.
This has consequences for the Concealment skill (last tier of the Physical category), where the challenge to unlock higher levels is making melee/unarmed sneak attacks. This is very difficult for hostile humanoid enemies, but is made quite trivial by these non-hostile fauna. Just go behind them, crouch, and punch.