I understand this would be a fairly difficult mechanic to integrate into the game, and totally understand that it would be a massive undertaking, but I’d be over the moon if some stealth mechanics could be added. Things like enemy line of sight, visibility depending on light levels on the player, amount of sound being made (such as different floor materials and movement speed making more or less noise), cameras being updated to be able to look at players/activate alarms, and so forth. Adding as much versatility for this in item properties for creators to adjust would be great.
And when I say enemies, this could be an entire “Enemy” entity created with voxels/meshes or even better if NPC’s ever become available.
Yes, this would mean an entire branch of gameplay elements would need to be integrated code side, but I can only imagine the possibilities it could create for people to use in their games.