Reddit mentions of Design Evolution: Theory into Practice

Sure, I think you would do well to go back and study the basis of visual design, concepts like layout, color, shape, etc... there is an underlying visual language to all design that allows it to express balance, define emphasis, create tension, lead the eye, harmonious color schemes, the like.

With just a quick google search I found this which is a good start. A book like this might help you put the concepts in context.

I would ( and have ) hired someone with a better design eye over someone with better skills, because if the person is diligent, the skills can be spruced up, someone with a bad eye won't see the innate purpose and is generally slow on the shorthand.

If you can, I would look around and try to find a college course like this and see if either you can take it or just sit-in on it. I think it would be beneficial to have someone teach you as opposed to reading books about it, because they can guide you and give you exercises to do that will help you internalize the concepts.

I go back to actively thinking about the principles very frequently, sometimes they're a real catalyst to that aha! moment when you get stuck. But most of all they're the basis for being a competent artist in any discipline.

It's the difference between seeing a very simple piece of art and "knowing" that it's just perfect, and seeing a really intricate peice that looks kinda cool, but somehow it's just wrong. You will want that simple truthful elegance on your side, and having the principles of design at your behest will empower you to create effortlessly rather than grinding something out that you're never really happy with. Not to mention, giving your work that little extra push into being great.