My main complaint about Kakarot was them just putting DBS in DLC instead of simply putting it in the game. It's definitely something that focuses on bringing out the nostalgia feels for big Dragon Ball fans, though.
It's extremely detailed about what goes on in the Dragon Ball story, even adding in non-canon things that happen between time skips. You barely get to play as Goku in the main story, which is ironic as the game is called Kakarot, but when you do, it feels like your power just skyrocketed, because you always switch over to him when he's hit a new power-up from training. I definitely like how the game isn't loosely following the Dragon Ball story, but actually makes you feel like you're in the story, even if you're just playing as canon characters. I also remember how hype it was to unlock a new form or watch a cutscene based around an important part of the story.
Honestly, the best part about Kakarot is really just making big leaps in power. The gameplay, while usually the same between each fight, rarely gets stale until you've completed the main story, and is overall very smooth imo. Except the Dr. Gero fight, that was really annoying.
You also see a lot more of the classic Dragon Ball characters than you would in any other DB game I've seen, and at the end of the game, against Kid Buu, it really felt like a great finale that really brought out my inner Dragon Ball fan from when I was a kid. That was definitely where I hit peak nostalgia levels.
Overall, I wouldn't say Kakarot is anything to write home about, but I do think it's worth playing if you have the money, enjoy RPG's, and are a fan of the series.