All of these tests are possible using command line tools, but some of them would require multiple invocations of the tools, as well as verification against a matrix of known-good configuration parameters. For example, the DNS report is pretty comprehensive.
What's surprising to me is that these tools are web based. Although, there is some value in having a third party verify your assumptions. It's not uncommon for me to alter my hosts file while I wait on DNS to propagate. That can screw up my resolver when running diagnostics locally.
