It took me a bit to place star of "UK Ghosts". And then I was oh Call the Midwife. Leaving Call the Midwife was a good decision for Charlotte Ritchie.
However, I still don't think they needed to kill off the character. Since they didn't have Tom come back to the show after killing off Barbara, they could have just written the couple out by having Tom reassigned to a different church. It's been a long time, but weren't Tom and Barbara absent from the show for a while until they brought them back just to kill off Barbara?