Cool idea! I think that you should definitely add some audio(sfx mainly), which would really pull this all together! One other suggestion is to make the particles come back slightly less after you've exploded them, because I found that as soon as I had cleared the board, all of my hard work got erased because so many more particles popped in! Just a little decrease would work(Maybe only 80% of the destroyed particles spawn in right after you clear them), but I think it would be helpful!