I like #3 better than #2, see comments on design #1 about the breaking down from larger to smaller chunks, with the "vee" given in #3 looking like it has some of those elements. I prefer the full name of the lab "Systems Design Laboratory" in the logo.
While I like the simplicity of #9 and #3, it does not capture enough of the design process. I like where you are going with #12, with bigger blocks at the top, going to small at the bottom. Any way to incorporate arrows?