I'll give this a shot..
This is a very warming song, and I definately like the use of a music box (which you said is meant to invoke memory), but you use it to invoke the memory of the worlds that are lost, this I like. I definately like the overall, *remember* feel to it.
I also like the use of the choir, and the part where the music box plays a more complicated rhythm.
However, I probably like the constant eighth notes better just because they help to depict a pleasent emotion better, however...the quicker rhythm does add some energy for these worlds, and it's always good to make sure it doesn't get repetitive.
Strings- Ahhh, I love the way you use strings in your songs, I am also a huge fan of strings, they add so much emotion for some reason. Mostly if your going for a slow, sorrowful, or peaceful peace (as you do).
Great song, I'll keep these worlds in my thoughts for you. I just wish i could visit them = ).