have a bunch of finarfin headcanons because this world needs more finarfin headcanons
his hair glows in the dark post-Darkening. It's a subtle golden light, though it can become more bright depending on his emotional state
he didn't have a patron while he was young, but as he grew older, his Valie of choice became Estë
he loves woodworking - when he was younger and lived in Alqualondë, he would often help in the docks to repair/construct ships
he loves the sea more then he loves the city, though for the long time during his kingship he would forbid himself to even think about possibility of returning there
He would always try to connect with his kids through shared activities. He would listen to Aegnor reciting his poetry and would sometimes go hiking with Finrod; he thaught Angrod surfing; he couldn't find an activity to share with Galadriel - she wasn't much of a team player and loved doing things by herself, so eventually Finarfin learned to step back and give her space she needed.
he is subtle - and also I apply Tolkien's "the hands of the king are the hands of a healer" to him a lot. He doesn't purposefully draw attention to himself, but he's always there. He makes sure every problem is fixed even before you notice it's there. He listens to what his people want and does it without a second thought.
He becomes close with Amarie. She is his right-hand woman, of sorts
He experiences hallucinations (more accuratly, psychotic depression) post-Doom. First he would hear laughter and banter in empty house. Sometimes it would be accompanied by music - piano and violines, the instruments his children used to play. Later, he would see his family, though they would never speak to him directly. He saw Eärwen a few times, and every time he was sure she was real - she was the only hallucination that never seemed unreal to him.
He suffers from chronic pain post-WoW
During WoW, his most used weapon (and most favored one) is his spear
