I know what music should play during Harry's death walk.

Bane

My Love is Always Here.

And why not?

It's amazing, but only faintly heard in Part 1. My reasoning is that when you rewatch Part 1 after Part 2, if the song were to play in Part 2, it would feel like a sort of hint of things to come and make the Godric's Hollow scene even more powerful and atmospheric than it already is. It would make Part 2 rhyme better with Part 1, and the song would completely match the visual of Harry walking with spirits.

Festax0333

i wann see what other masterpiece desplat comes out with though(:
but yeah that would be very satisfying

Bane

Well, that or Desplat could do a stronger, instrumental version of it.

blackvenom

I expect a choir during the Forest Again sequence. Actually I think that he'll use a lot of choir in Part II. During battle sequences, during the scenes with all dead people and destruction, during Potter's walk in the forest.
But if he uses My Love is Always Here, it will be amazing.

KJRiddle

An amazing idea, but as darthorcrux said, Desplat should (and is definetely able to) make a stronger, better and less bombastic instrumental version of it. But the Mother Mary-Baby Jesus/Harry and Lily-reference is appropriate here, so why not? He could even use that song to make a Part 2 'Lily Theme'.

silverarrowgriffin

My Love Is Always Here is good but it sounds like 'Christmas'....maybe another choir/instrumental track