It's difficult to know what was going through a writer's head when they penned a particular sentence; in this case, I suspect that the writer was trying to incorporate a phrase with the same structure as lion of a man, (noun of a noun).
A man can never be a lion, but can personify the qualities of a lion. Ditto with Clinton:
Clinton was a "status quo" of a candidate.
We have something that is grammatically correct but already it does not sound natural.
We normally use more with an adjective, but it is also possible to use it with a noun, for example
More man than you'll ever be - Aimee Allen et al
Using a noun phrase in place of a noun in this construct is still grammatically correct, but even less natural.
The icing on the cake is negating the whole lot: the resulting sentence is still, amazingly, grammatically correct but it is far from a natural construction.
Your proposed alternative is certainly more understandable, but there is an easier way to improve upon the original: leave out the of, and put status quo in quotes to make it clear that we are referring to the previous occurrence and using it in an adjectival sense.
....there was arguably no more "status quo" a candidate than Clinton...
This construction is literary but fairly well understood, for example:
The death penalty is no more effective a deterrent than life imprisonment. Encyclopedia of Capital Punishment in the United States, 2d ed.
As a general rule there is no more honest a man on earth than a bookmaker. Rhubarb