I don't think that makes it simpler. I think that just makes a massive compositor which tries to please everyone and ends up pleasing no one, and being 10x the size it needs to be.
Ultimately the compositor IS the desktop environment. You can try all you want to keep it simple and enable functionality via other apps using a protocol, but that's essentially a complicated way of making plug-ins to the compositor. You will end up delegating security to everyone else.
That's not true. It's true for GNOME, and I guess Enlightenment, but they are not the only players. If you think there are legitimate security concerns with our approach then I'm open to hearing them but so far as I'm concerned so far you haven't said anything of value.
We don't need modular.
>>>BTW, I'm hoping for animated wallpaper on my desktop
>> This is possible with the layer shell protocol I'm talking about.
It's also possible by building the feature into the compositor. No new protocols or possible security issues needed. Simpler is better in most cases.