I normally dislike "waif fu" stories of the petite little cutie who beats up great hulking fighters ten times her size. Yet this turns out to be a surprisingly enjoyable story with a feisty and sympathetic heroine, once you get past her "uncanny valley" bug eyes (are they fortelescopic vision? Low light gathering?). I found myself drawn into Alita Battle Angel’s richly drawn and portrayed dystopian world, and the various cast of heroes and villains, not all of whom are as morally black and white as first appear.
The influences / parallels are obvious (the old standing on the shoulders of giants thing). Bladerunner, Ghost in the Shell, the 1970s movie Rollerball, and of course the whole Lost Technology of the Ancients trope
Interestingly, Alita and Captain Marvel came out at the same time, and both share the same trope of the amnesiac superpowered female warrior. But Alita is a far superior movie, both in storytelling, depth of character, willingness to kill off important character(s), and originality of worldbuilding.
I haven't read the manga or seen the original anime the movie is based on, but as gritty YA genre (with teenage protagonist and love interest) this is pretty good stuff.