Rescue seems to be the consensus!
Is there another course (other agency?) which adds diver skills? I'm thinking about the self reliant diver, which is what my uk based agency (bsac) teaches.
Shame that buddy diving can be so poor.
There are lots of courses that add skills but it is based on what type of diving you will be doing. A wreck course can be great for learning to lay line, touch buddy procedures and learning how to identify possible hazards.
Search and Recovery is a course I did not think I would ever use but then I had a test on a dive boat drop their computer overboard. Down I went with a buddy after making a plan, ran a search pattern taught in the course and surfaced with the diver's computer.
Navigation is always good to learn for when you are doing dives where you need to get back to a certain point.
The list can go on but you have to look at what diving you want to do. I would suggest sitting down with an instructor you trust and talk through these things. Any good instructor can put together a list of courses tailored for what you want. Some will also put together a workshop where you do not get a card but get to learn the skills you believe you will need in the future.