Right? It just doesn't sound right for my ears. Even when i listen to the intro part to many covers, it feels like... something lacking? Something that only Suisei's voice has. Even none of them can hit Kanaria's voice. Imho, for now, i haven't found a cover that can reach 85%
it's something about the mixing as well i feel! kanaria and susei are backing vocals for each other, but they're mixed in such a way that it's difficult to distinguish. a lot of the offness i feel tends to come from that as well.... there's something 'missing'
If I had to change something on Suisei's drawing, it'd be the eyes' white part, which i think should be grey/darker, similar to Kanata and Laplus' since the overall drawing is pretty dark. But good job on drawing it, it looks and sounds great as always!