I approach this situation from the opposite viewpoint....
I want a few knots (or hitches, bends etc.) to fulfil a number of tasks;
1, Attach a cord to a strong point
2, Attach to itself and slide to tighten/loosen a loop
3, Attach to a second line and move/grip as required
4, Tightly bind a compressible bundle
5, Secure two ends of cord together either the same or different diameters
... if these can be achieved with a "slip-finish" to allow easy un-doing, then so much the better
Add in a few knots of specific use and some decorative elements and I should be good to go!
What these knots are in actuality is open to interpretation at the point of use - I have been tying knots since I was a Cub Scout some forty odd years ago, certain knots remain as useful, others rise and fall in popularity as the mood takes me.
ATB
Ogri the trog