I'd say in regards to the music, the low full bass notes are a bit too low in my opinion. I like the accents in the higher note parts and I think having more things like that throughout the song could help it feel less repetitive since it's in a looping game. Sound design wise I'd say a a shorter noise rather than a full "sip ahh" sound would work better since you can collect so many so quickly that they tend to overlap on each other or cut one out. As well as having that AND a ding noise might be overkill. Something just like a quick sizzle noise may work better :)