I have problems with knots, I am terrible with them, despite having some books. I think what I really need is a flowchart (what are you tying to what else? what kind of cordage do you have? what kind on the other end, if applicable?) with a list of knots at one end, with their various strengths and weaknesses. The jargon is a bit of an issue, too.
If you want to expand your list a little, here are some additional useful ones: double fisherman's, adjustable grip hitch, sheet bend, trucker's hitch.
Edit: I suppose this is more useful with a little additional commentary. The reef knot is so common that you should know it and know how to avoid the granny knot and also when not to use it (e.g. as a bend). You can use the alpine butterfly as a bend and also for quite few other things. It is more versatile than the bowline (e.g. if you need a loop that doesn't slip) and works fine as a bend (very smiilar to the Zeppelin bend).