I'm gonna get this comment out of the way: this game would go so hard if it had bgm. The sfx are pretty good already, and the gameplay is pretty solid, but with the right bgm this would have really hit a vibe.
But, like I said the gameplay is pretty solid by iteslf. It's nothing terribly new, but I did appreciate the indicator that showed the range you can link the balls to each other. It helps with planning my route across the board. I think you could have lowered its opacity a bit that way it's a little more subtle but still there. Although that's not really a big issue especially since the outline's already only a pixel wide.
I didn't get too far, in the game because I had limited time, so I didn't see if there were more complex recipes that required more than 2 combinations of talents. That's maybe something to consider in the future, if you haven't already implemented it. Also, probably worth working on making the game with scale-able resolution instead of imposing fullscreen gameplay all the time. I think the character balls are still distinguishable even when scaled down (good job on the art, btw) so I think the game is still pretty readable in lower resolutions and gameplay won't suffer.
Lastly, and this is maybe a preference nit pick on my part, but I think the range of the Holo Ball explosion is too big. It clears more than half the screen and gets rid of a lot of balls I was saving up for a combo. It's practically a board reset, and at that point why not just make it a board reset. I think you may have done it so that even when the Holo Balls sink to the bottom they can still hit the hearts that are stuck on the top of the board, and if so then I totally get it. So if you are looking to improve this game post-jam then that's maybe something you might wanna take a look at and see if there's anywhere else you can improve regarding the way the Holo Ball works.
But, I mean, if you're happy with what you already have and it's aligned with the vision you have for the game then don't let a single person tell you what to do, right? ;>u< I think you're game's still pretty fun as it is. Good job and congrats on the submission!