There's a lot (or maybe just some) code that depends on plugins being in Piwik\Plugins. For example, the name of a plugin is obtained from the namespace by looking for Piwik\Plugins{Name}. Maybe DI can be used (ie, Plugin objects are added to DI, and these objects are used to determine all needed info). So we don't have to care about what namespace or folder they're in?

Maybe DI can be used (ie, Plugin objects are added to DI, and these objects are used to determine all needed info).

Ideally yes! In the config there's a list of installed plugins. I guess that means that we can use it for finding plugins instead of relying on the naming. Then later we might move that list into the DI configuration.

Ok, for the 'get plugin name from namespace' issue, we could do something like:

foreach ($pluginsLoadedAndActivated as $plugin) {
    if ($plugin->getNamespace() == $namespaceWereLookingFor) {
        return $plugin;
    }
}

Not sure what other parts of Piwik depend on the plugin namespace.

I'm not sure there are enough benefits for the cost involved of changing it. Moving to mid term. let me know if you disagree and think this is more important