Love the idea of random buff/debuffs while playing, but they feel quite tame for a buff/debuff. Maybe it's because there's a limit to them, but it'd be funny if there were like 30 buff/debuffs at once. It seems like some buffs/debuffs can also cancel each other out, so sometimes it'll feel like normal gameplay.
One idea I'd suggest is have multiple taiyakis spawn after some time as a difficulty increase. For example, a normal taiyaki and pink taiyaki both spawn at the same time, but the player should prioritize the pink one or lose a life.
But anyways, great job! It's a very fun and cute game!