This is just a random posting about designing and ideas... I like designing new patterns as much as I love knitting old ones. Desingning knitting patterns is EASY, getting a new idea and then drawing your idea down is not hard at all. I have a few booklets of ideas and designs and random sketches of stuff I want to make. Having a sketch book is necessary :)
The hard part in making patterns is the knitting according to your design. Where to add stitches, where to decrease them, where to change colors etc... etc... And here comes the part I don't like, knitting and re-knitting the same piece over and over again is just a pain in the neck. But in order to achieve the result you want, it is one of the things you have to learn while designing and modifying patterns. In Finland we have a saying: No one is a blacksmith at the moment of birth. (Well that's the general idea of the saying). All in all turning good ideas into a pattern needs work and patience.
ps. And sometimes when I have an idea of a design and it is too hard for me to knit, I leave it be and after some time (and after learning a few new skills) I return to my sketch book and try knitting it again. Like the boots of my winter bear or the legs of my Seagull pattern (in Ravelry)