This game is actually incredibly polished. There are a lot of little animations that add a lot to the sense of production value, such as the results text after every stage, or the little animations when selecting love or hate after every stage, not to mention the animated intro and exit cutscenes too!
The sound effects are also on point as well and integrated quite well.
The gameplay itself is a great idea and watching all my otomos and grems fly around into the enemies was fun to watch (it helps that grems are very cute). It was easy to pick up and satisfying to play. For a game jam, giving off a cool vibe and a unique idea is good enough. And I could see this being a flash game being played back in the day.
If I were to pick out some points. I think the biggest thing that could be improved is mid-game actions. I found that I was able to get the best results by using the middle click buttons to send all of my grems/otomos charging at once. The fact they were all moving quickly meant that they had a high likelihood of running into an otomo or grem and dealing at least some damage. I don't know if this is definitely the best strategy, but it worked well enough for me to be able to run through the game without really needing to worry too much about my unit composition.
The game provides options to send just one unity charging at a time. However, due to the chaos going on, I found that I rarely needed to use the feature as it was just easier and more time efficient to just send my entire army charging at whatever I needed to charge at.
As other people mentioned, I think playing as Grems is a bit harder then Otomos. This is mainly due to the Otomo types being able to take out or damage large groups of Grems at once. However, I was still able to beat both campaigns using middle click spam.
Regardless, I think balance is one of the hardest things to do, and often something that can be very difficult to judge without playtesting. I also am not sure if my strategy is indeed the best strategy, but it was one that worked well for me. I think this is a very polished and complete feeling product, and most importantly I had fun playing it.