So as an anime fan I'll give a hint on terminology if you want to take an approach at it. What you're talking about is the genre Shonen which is targeted for boys in school, roughly translates even to "young boy." Because of that it's the ones that you have a group that's relatively easy to cater to... hence drag on for ever and ever like US comic books. There are a LOT of genres in anime like there are in western tv and it'll still be a YMMV because completely different culture, but because of the medium there are still some small studios that are willing to do some stories that are difficult to get in western media because it's too risky for corporations (granted that's been less the case with streaming coming out)

The number one that I'm sure anyone would recommend if you want to make an attempt is Cowboy Bebop because it's a good blend of western sensibility, it's a noir in being a group of down on their luck bounty hunters in space, set to a jazz, blues and rock soundtrack and has a good English dub from an era back when that was rare. And importantly, the story ends.