I read cozy and historical mysteries, a bit of Paranormal/UF, and to mix it up, I read science and gardening books on occasion.
I enjoy this series a lot - it's cozy without being twee, and the mysteries are reasonably well plotted most of the time. I also love that Kuhn shows way more than she tells; this might be the only reason I'd tell someone to read these in order. The stories don't require it at all, but the author doesn't waste her established readers' time by going over all the backstory. New readers might feel lost if they started with book 3 instead of book 1.
The Spirit in Question isn't anything I can rave about, it was just an enjoyable story. My first inclination was to give it 3.5 stars, but that's more a reflection of my bias against mysteries that take place in the theatre. It's a haunted theatre though, so that gave it an edge for me.
The plotting was solid; I had no idea who the killer was. But on the other hand, the motive for the killer felt a little weak. Possibly, maybe, one that unconsciously falls back on an old stereotype that feminists would grind their teeth over. It didn't bother me, but I did notice it.
My only complaint about the series overall is that she doesn't write them faster. I need more solid, dependable cozy/traditional series in my life like this one.