Cassandra Cain is one of the more legitimate (not cheap- female knockoffs) in comic books and might've been the blueprint for X-23, another good spinoff character

 

Batman v1 567

Excellent debut for the character, you get everything you need to know about her and a good cliffhanger.
She (Like Superman-Prime) doesn't get the exposure she deserves, and that isn't entirely a bad thing, the worst thing that can happen to a character like those two is they get mainstream & enter the realm of overrated hype-culture for the wrong reasons.

At least in this respect, being obscure, under the radar: Less opportunities for a gem to be tainted or ruined by the larger sphere of normie-isms and political correctness.

The better examples of quality in a medium tend to be underrated one's anyway.

C.Cain is an underrated gem

Detective Comics v1 0734

And the best part about her being able to keep up with Batman, is it makes sense narratively, the entire point is she was drilled so hard, so intensively she wasn't even permitted a language to speak as a child- So for her to cut Batman's gauntlets with simple attacks, and it makes sense, for being so young? She is definitely unique as far as a Batman Family member goes, especially being one of his partners in the field. 

So she learns from him, mentored by Barbara & Batman ONTOP of everything she already knows. She has to be top 5 greatest fighters in DC, easily. Especially if /when she eventually rank above her own mother. Her origin story/ overall existence is really something special. 

Not sexualized, not second fiddle, no direct relation to Batman, her history is built upon that fact that she herself is interesting without riding coattails. Not a miracle blood relation or her being a glorified pin-up girl that's desperately been re-envisioned to be deep when she really is not. Cain suffers none of these issues, in the brunt of her first few volumes to say the least.

This is the execution Kara Bore-El is missing in every single respect & area in comparison. Thus it confuses the ever loving crap outta me how Supertoken gets so much push but Cain gets so little to work with- Overrated gimmick vs Underrated gem. Cassandra Cain is solid, her lore is intriguing and so is this 2 issue debut for her character (Batman 567 / Detective Comics 734)