I've got 200+ hours on this game, so I may be a little biased but...
Its peak fiction.
First things first, let's talk about the main part of the game: Characters. These are definitely the most creative, fun, elaborate, and well made characters I have ever played in a platform fighting game. Each character is so unique from one another it's insane. You could be playing this game for hours and still find new features in your character.
Second: Stages. I will admit, stages aren't as memorable as stages from say, Smash Bros. But I would be lying if I said every stage doesn't look GORGEOUS. Every stage is beautiful in this game. I could go on and on about the artsyle of the game as well. Gameplay wise, there could be more.
Third: Music. Again, the music is DEFINITELY not as memorable and Smash Bros. music, but DAMN does this game have some absolute bangers in the ost. (Land of Ooo or We Are the Crystal Gems Synth Remix are my favorites). The rest of the ost isn't as memorable, but you can still enjoy a lot of them.
Fourth: Content. I REALLY love the customization in this game. Being able to have character costumes, ringout effects, badges, profile pictures, profile banners, etc. Really lets you express yourself and I love that. Battle passes have some really good content in them, and the paid side of it isn't necessary at all. Only if you really want some extra costumes or taunts.
Fifth: Modes. 2v2 Teams Mode is the main mode of the game for a REASON. This mode is such an absolute blast to play with friends. Each character being able to provide buffs or debuffs to other characters never leaves a dull moment. 1v1 is just as good, but not really my thing though. FFA is where the quality takes a dip in my opinion. It's a little too chaotic and random.
Extras: A little off topic, but I LOVE how amazing Player First Games is treating the community and the game. They take a lot of players' thoughts into consideration. The controls in this game are so smooth. The only negatives I can think of for the game are that the online can be a little to very laggy at times, progressing through the battle pass/character ranks takes A LOT of time, and rewards for playing matches are really small. People complain about the game being dead, which I'm not sure if I agree because I can constantly get into games. Plently of people love the game still.
Conclusion: This is definitely up there in my top 3 favorite platform fighters. I know it was recently announced the beta would be closed in June to prepare for the launch in early 2024, but knowing PFG and the game they've brough so far, I believe their official launch will be amazing.