If you want to praise JoJo I think you would talk about its sense of humor combined with its unique narrative, especially the visual aspects of it. Like, it is fun to watch a vampire whose head was just split in half putting it back together, but having it a little off, so he has to adjust the two pieces, which seems to make him slightly annoyed.
Even better is to watch two dudes fight, where one throws a steamroller at another, and then both repeatedly punch it to make the machine hit the opponent. There are hundreds of awesomely stupid things like that in the series, and they all work because of how the show presents them. It is not all about actions scenes either, this anime can make even a static image work. Like this one, when an ark antagonist assumes a ridiculous pose and the anime treats it like focal point:
The whole anime is like this. People act as if they are actors on a stage, they strike poses that look like they belong to an athletic dance performance; the events are unpredictable and ridiculous while the characters are always in dire predicaments. You never know what would happen, would they outsmart their enemy or would they just overpower him or her, or will they get out on a sheer luck.