I totally agree with everything you said. I liked the episode, but if I didn't know the show before I don't think it would have "hooked" me to it. I really don't understand why they feel the need to change everything every season. The old shows like Starsky and Hutch or the original Five-O or Star Trek worked for years with the same formula applied again and again and that's why people loved them. I miss Steve and Danno and I miss Kono, a lot. I don't hate the new girl (she looks a lot like my sister!) but I don't see what she's doing here. I like Joe a lot, and as you said, Steve needed someone like that in his life. I don't think anyone could cope with everything that's happening to him without some kind of reassuring person to rely on.
I hope it's okay I commented on your post. It felt good reading your words, feeling not alone - H50 is my "escape moment" in the week, I need it to stay as good and reliable as it was!