With this journey of handspinning, I am reaching for a level of facility where I can easily do with the fiber what I do with food when baking.
I can eat a scone, take the biscuit recipe I use, and come up with a scone of my own by altering the biscuit. I can take my usual carrot cake recipe and make it chocolate-flavoured, then make it into different sizes like cupcakes and enormous sheet cakes, and then from there come up with a sugar-free, dairy-free, wheat-free chocolate carrot cake. I implement substitutions or techniques that make sense and produce what I want out of what I have.
I can do this somewhat with fiber already.
I don't ever expect to buy a knitting kit.