As for the Holy Sepulchre, as a non-Christian I found it pretty surreal. Clearly for the faithful it's a big deal, saw people outright crying coming out of the Sepulchre.
The church itself is beautiful, powerful artwork from all of the sects (Ethiopian included). Particularly the fresco at the entrance, Christ being laid to rest, the disciples in tears, pretty moving piece.
Unfortunately my experience was darkened by a group of troublemaker teenagers; saw them shove an old woman deep in prayer, just appalling. On leaving they followed me and one of them spit in my hair. When I turned around the kid said, "only water, only water".
Needless to say Jerusalem's a complex mix of cultures, history, and religions.