Curate, connect, and discover
The biggest reason Cass is the only natural option as heir to The Batman comes from the fact that every other character’s growth relies on them at some point either removing themselves somewhat or completely leaving the Bat symbol behind. Cassandra is the outlier whose found a reason to live on as that same symbol.
We can argue day and night who the best vigilante, detective, fighter, hero, strategist, or whatever is but none of that changes who can survive being the symbol without losing themselves in the process of following Batman’s footsteps.
The amount of times Jason has stolen one of his siblings costumes and murdered in it is insane. Like I’m pretty sure the only ones he hasn’t done this for are the girls and Duke.
Jay as Nightwing
Jay as Batman
Lastly, Jay as Red Robin and while idk if he killed anyone in the comics
He definitely did when he wore the outfit in that Death in the Family movie thing.
I always think Dick calling Jason “Little Wing” is hilarious given one of Dick’s primary grievances against Jason is that Jason has a habit of putting on the Nightwing suit and killing people in it