I recently found myself in the position of describing (or rather, comparing) two different Catholic churches, to help someone who is traditionally minded decide which to attend. As I thought about it later, the kinds of things that I chose to mention were interesting, and certainly say something about a church. But most people wouldn't consider most of these things significant at all! I hardly even had to mention the devotion to orthodox Catholicism, since the interesting thing is that these things all point to that!
-Of course, the quality of the music. How much chant? Anything in latin? The quality of the choirs and of course what styles of music they sing in.
-The demeanor of the priest while celebrating Mass; including, how much he "ad libs," or brings his personality into the ritual.
-The content of the homilies.
-Whether there are female altar servers.
-Whether the church "looks" like a church inside.
-The demeanor (lack or presence of chatter or respectfulness) before and after Mass from the congregation.
-What kind of vestments the priest wears, and what the altar servers wear.