Another thing I thought about was the ability to write and change extensions right from the admin. Because people have different needs. This could be possible without chmodding.. just by storing the edited extension in the DB(with xml). When you later overview your extension list, you can see a small this-extension-have-been-edited notice in those rows where you have changed code for the extension. It could also be possible to revert the changes back to default if you chose to. But that may be too bloated for PunBB.
We have plans for this. It won't be included out of the box, but we will offer an extension for making extensions. With it, you will be able to edit existing extensions as well as create new ones.
On a related note, Kristoffer (aka Jansson) has been working on a Windows application for extensions authors. It's really cool. Maybe he can show us a small demo?
"Programming is like sex: one mistake and you have to support it for the rest of your life."