It's very difficult to write tunes that are strictly chiptunes while making them complex and engaging enough to be listened to as standalone music. Unfortunately, sticking to a fixed sound palette does make a track sound repetitive, even if there's no actual copy-pasting going on. I do notice the subtle variations between the loops in this remix, but they're quite subtle. 1:08 sounds too much like a return to 0:11. The fade-out ending adds to the feeling of repetition.
It sounds to me like you're not sticking to an authentic GB sound anyway—to me, the reverb sounds richer than what the GB could produce, and it feels like too many layers—so you might as well go the extra mile and use more tools than what it had. Change up the synths, strengthen the kicks. It's a good start, though.
NO