In the past couple of days I was reworking my mediawiki dev setup, and I think it might be useful to the script runners/writers as well - an auto-configured (vagrant) linux virtualbox without gui and with all dev files residing on the host.
All dev files reside on the host and are simply mapped as a /srv/... dir in the client, all editing can easily be done on the host using whatever linux/windows/... tools users prefer. WinPdb sounds like a good remote debugging solution. Because it is possible to auto-configure the virtual box, we can set it up to have git, gerrit, unit testing, and all other tools needed for communal work. The box already includes a basic mediawiki installation, so devs can try out their new scripts on it.
Also, very importantly, we can have very simple instrtuctions because everyone's environment would be identical.
> "vagrant up"
> ssh to the machine
> run script or git pull or git-review or browse to localhost:8080 or ...