Great characters have strong opinions
Passion, opinions, experience
Characters need desires
Stakes should be big and conflict should change something emotional within the core of the characters
If your characters have to stretch their skills to overcome conflict, the conflict isn't big enough. They need to dispense with baggage entirely and build themselves anew
To make emotions land, set the opposite expectation. Just like In architecture.
Double climax. Life or death action followed by emotional resolution
No such thing as a small character. Think of rowan Atkinson in love actually