We have given up completely on Wired Tests. We have built an extension for Arquillian to allow in-container testing for plugins https://bitbucket.org/Adaptavist/atlassian-arquillian-containers for an example of how to use it see the the Adaptavist reference plugin.
It supports all injection, including scanner annotations, running code inside the application, and outside. We are much much happier with this approach than wired tests and as a bonus it is possible to use webdriver extensions Drone and Graphene. The next phase of development is to support container deployment with Arquillian Cube to allow us to use the selenium docker containers and to start and stop Atlassian applications with real databases in a fully managed way.
As far as I can tell Atlassian have pretty much given up on wired tests, there doesn’t appear to be any progress for quite some time.