Heyday is only edged out by Priest=Aura as my all time fave Church album. For me it's the sound of a band reaching a destination (not directly) which they began with Of Skins and Heart.

As for the horns and strings- I think it's a nod to Forever Changes by Love, one of the greatest psychedelic albums ever with heavy, often paranoic references to time and existence.

I love every track off the album (even Youth Worshipper!) and Myrrh will always be the opening track to my ultimate Church compilation.