I suffer from reduced color vision (atypical trichromy). I cannot complete any of the the "Insight" challenges, as I cannot see the runes to activate them. That would be fine (not all realmwalkers are made the same) but I cannot complete the main progresssion quests as a result. I'm trying to complete "Where Angels Fear to Tread," but cannot get through the quest.
Please don't color-gate the game.
Even for those who can see colors clearly, one marker is often maliciously hidden, making it unusually difficult to find, and even more difficult for those who have difficulty seeing colors.
Also, as I was playing, I noticed that the puzzles with sequential sound sequences would jump up the difficulty level for deaf players.
I think the puzzle elements should be like a breather.
If the creators really want to make puzzles mandatory, I think more consideration needs to be given to a more diverse group of players, including difficulty.