Well, the latter obviously works within our definition. That's like writing off the Soviet Union when asking about a 'bigger Russia.' True, it isn't exactly the same. But the fact that Russians dominated said union, would allow us to use it as an example. The same way, a Maghrib with Morocco holding the power still fits within the demand of the OP.
Except that with a state encompassing all of the Maghreb, "Morocco" isn't holding the power because there is no "Morocco".
It's not like the Kaiserreich where one state is the overwhelmingly largest component or the USSR - you butterfly the development of Morocco as a kingdom apart from the neighboring lands by creating a pan-Maghrebian state that lasts.
There's no basis for "Moroccans" as a distinct people from "Algerians" there in the sense there is today.