What non-technical skills add significant value to system and network administrators and designers?

Project Management (You'll be doing a lot of it)
Communication (Especially to non-Technical people, translate nerd speech to human language)
Problem Solving

patience and communication. When dealing with technically challenged people, you have to learn to to communicate on a level they understand to determine exactly what they want, of course without making them fill like they are challenged. A daunting task for most in the IT community.

The most significant skill in any job is the ability to communicate. Miscommunication leads to conflict. Poor communication leads to lost opportunities and confusion. I openly admit that I have succeeded in five different careers far better than I had a right to expect because of my ability to speak to an audience, hold their attention, and convince them of the merit of my proposals (even when those proposals weren't as promising as competing ones). My ability to use the written word effectively has also produced similar results. Now, in my retirement, all I'm left with is my facility to communicate and I've taken up the craft of storytelling. I love it...