antifascist themes? 
environmental preservation subtext? 
coming of age story where characters actually act their age? 
che guevara character that monologues about what the events mean? 
FLYING SURFING MECHA? 
banger fucking soundtrack? 
ok downsides are - the first 10 episodes are pretty rough honestly aside from the first two. weird 2000s anime tropes and some anime weirdness with women but this does develop out well as the characters do. some of the characters are strange stereotypic designs (black guy who djs and wears basketball shirt) but the characters absolutely are not standard tropes in their own way.
either way i recommend a watch and try not to cringe too much during the first arc
yeah with some decent world building and good character arcs aside
never seen xam'd, but that looks interesting. bones in the early 2000s was cooking