[lolinder]

> Now you benefit from both, like being able to make the lights fade off/on.

Dimmable smart switch plus dimmable standard bulbs accomplish this. No color (though Phillips has a line that tints red when dimmed.)

[ethbr1]

Is there anything that does PWM data over powerline to control lights?

That seems like the best of all worlds.

Networked smart switch. Switch in absolute authority of light. Switch still able offer advanced light features (e.g. hue set).