As the title says, the vibe of the show is pretty light hearted and the setting is quite idyllic and sort of alt-historical (early 20th century England). So, there is an appealing escapism aspect to this show that keeps bringing me back.
That said, how the stories play out, the way they investigate and figure out who did it, etc. Has gotten quite repetitive. It's identical in every episode so far. This is not Sherlock or Poirot level. It can also come off as too light hearted, well goofy, sometimes, think they could dial that back some but it varies by episode.
Like many mystery shows, Sister Boniface doesn't solve the mysteries on her own, there are 2 official detectives plus a tabloid news reporter who all play parts gathering clues. Sister Boniface just always plays the most important part piecing everything together towards the end. Most of the acting is pretty good given the nature of the show.