I'd have to add that the Quatre Communes was somewhat of an anomaly, and not in any sense viewed as having a broad application. Suffrage - *Not* citizenship- was granted to the residents of the quatre communes in the midst of the radical backdrop of 1848, and was confirmed in almost a bureaucratic inertia in 1873. Ill-defined rights of the African orignaires was often undermined and limited by the governors of Senegal, and later, governor-general of the AOF. Clear definition and of the rights these around 20,000 orignaires' status as a citizen was only reaffirmed by the Diagne law of 1916, made possible under exceptional circumstances, i.e. WWI and conscription drive in West Africa headed by Blaise Diagne himself.
Now, integrating entirety of West Africa, applying the AOF border, is simply unthinkable. Even Senegal proper is highly doubtful. The reason why Algeria was integrated - "integrate" is a dicey word, millions of Muslim Algerians were most certainly, not integrated- to the metropolitan administration was because of the sizeable European population and future plan to create a settler colony in the region. OTOH, West Africa did not saw any significant settler population, nor were they viewed as a place to be settled in the first place. Even in large urban centers like Saint Louis and later, Dakar, summertime saw a drastic reduction in European population due to perceived hostile climate.
One of the big myth of French imperialism is this idea of "integrationism" versus British "delegated rule", this is a complete load of bollocks. There was no meaningful effort to "integrate" the Africans to the "French civilization". Even in Algeria, the percentage of "Muslim" pupils in the elementary school during the early 1950s was around 10%. In AOF and even worse, AEF, it would have been in low single digits. It would have been a monumental undertaking and would require an ASB-level change to the "acceptable" level of French political discourses and even French political situation. IMO, even in a situation where French government abandons the Metropole, it wouldn't have happened.