GitLab B.V. CEO here, thanks for promoting GitLab at work. I'm sorry to hear the installation was a painpoint. Have you tried our packages? It is a single file that installs in two minutes.
I absolutely love the product. The install guide is fantastic, I don't know if that can be any better than it already is. The thing is, I'm a little paranoid about downloading & installing random binaries on our computers at work (I work in a very IP-sensitive company), so I generally go for source-builds.
I've actually been writing a fabric script to automate the entire install, believe it or not (the whole thing might be an exercise in futility, since people could just download the package), and I've installed gitlab enough times that I'm not really worried about it -- so at this point it's not a huge problem.