i've got a couple but heres some of my favourites !!
uhh so i think Soul removed Heart's eyes, not Mind.
I personally interpret FIF as Heart and Mind, as well as the before. as the predecessor to the events of CCCC. i know its not canon but i interpret it as such, as well as The Man with the Skeleton Arms being about Mind and their mechanical hands.
I think at the end of Just Apathy, mind maybe feels a little remorseful. just a bit. specifically the line "I'm only happy when all I see is the back of my eyelids", since heart is HEAVILY overpowering Mind in that verse and mind kinda seems to go quiet almost. also they totally cried or almost cried in Storm and a Spring.