Hang in there. I could say more, but I know you well enough to know you won't listen. I like the extended family that seems to grow with each book. They don't all get in each book, but I try to include people she might naturally encounter in a story. Yes, it's a challenge, as is it in any series, to bring back characters without also bringing in too much history, or bringing the story to a grinding halt with a lot of references to previous tales.
Locations are very important in some ways.
Irene is in a good-sized beach city. Not a little village or town on the shore. Southern California beach cities have this image of being sunny and bright places to play. It's also on the Pacific Ocean, has a major harbor, and is close to an island. So it's flexible in terms of terrain.