I think Final Squall should have been the main A-Side. Singing ~Ano Koro no You ni~ Should have been on this single rather than the last one. And then To Tomorrow as the 3rd A-Side.
As much as I love Mugen Climax. Its not as much of a Good Bye song. I'd rather the last single be more underwhelming and good bye feeling. That way I cry less about the group disbanding. Its kind of selfish, but I'd rather not end with wanting more from the group. A clean break hurts less. I'll stick with the nostalgic melancholy for the final single.
Also the Curtain Rises would have been better packed with Mugen Climax. Similar vibe. And the two singles would be more balanced in general.