I'm a computational biologist that recently ported our webserver (genestation.org) from Tripal (PHP/Drupal) to Go. The performance gains were huge, but the simplicity of development and deployment was even better. I'd strongly recommend Go for a biology web server. However, Biogo is not remotely as far along as Biopython or Bioperl. Also, Perl beats Go for ease of string handling. Unfortunately, there is no equivalent to Numpy/Scipy in Go. Despite these areas of weakness in the ecosystem, I have switched to Go entirely except for one-liners and one-off parsing in Perl.
You said above you 'may start rolling your own packages'. If you're interested in helping develop the numeric ecosystem, please come join us at gonum https://groups.google.com/forum/#!forum/gonum-dev github.com/gonum.
Dan (the lead developer of biogo) is very competent and I'm sure would love bug reports and PRs in biogo as well.
Chado does have substantial performance problems for use as a webserver backend. We use elasticsearch for full-text search and as JSON document store, which improves performance substantially.
