I like characters who try to give off tough guy vibes so nobody notices what they're actually struggling with (examples in television include Rosa Diaz from Brooklyn Nine Nine and Jamie Tartt or Roy Kent from Ted Lasso, in literature I can only think of Grantaire from Les Miserables because I haven't read fictional novels in years)
Similarly, a favorite relationship dynamic is enemies who become not enemies after the one with more power in the situation learns the other is being abused and the other is so confused why somebody who hates them gives a damn.
Its just... wish fulfillment to the highest extent (i don't have anyone who hates me in my life but even the thought of acquaintances realizing and caring that bad horrible unwanted activities occur behind closed doors... impossible to believe would occur IRL so I create those exact scenarios in fiction)
Trauma responses are a favorite part of characters to write, particularly because they can directly contradict each other - competing access needs causing the enemy-aspect of the above mentioned relationship is yet another trope i love writing, like when one character is extremely quick to anger and the other shuts down amd shutting down makes first character feel unheard and even angrier only second character is actually dissociating because people being angry with them usually leads to violence or emotional abuse.
Sorry if these responses are TMI and you were hoping for more light-hearted stuff.