This is Jules Ferry, right? Because if you can kill him off before the push for his education laws begin, then France's minority languages (especially and most notably Breton and Occitan) might be in a hugely better place since I've often seen Ferry's education policies blamed for their decline.
That's in addition to colonialism, which Ferry as you said helped set the pace for. Could Madagascar survive as an independent state without France colonialism? Especially since it was doing quite well on its own (a modernising state akin to Thailand) and is a natural place to have a holdout against colonialism as a unified island state. And if colonialism in West Africa/Sahel goes slower, then there's a strong chance for powers to hold out until the Great War. I guess it depends if there's anyone to take up his mantle after his death.
Ferry was a figurehead, one of the most important leaders of his party, but his points of view were widely shared in the french political elites. The colonial expansion was already booming during the Second Empire (3x colonies ; for example heavy french influence in Madagascar 1853-1863). Many leaders, even in left-wing parties, shared the creed of "civilization brought to the inferior races", save for few exceptions such as Clemenceau. The death of Ferry could have consequences in the rythme of colonization, as he was a proponent of a maximalist, deliberate policy of expansion, while others, such as Gambetta, advocated an opportunist, reaction-only colonial expansion. So maybe a less extended french colonial empire, but a colonial empire nonetheless.
On the local culture thing, Ferry's reforms of free and mandatory schooling were not as influent as it is commonly thought of. Before Ferry, there was no minority language schooling, so he did not destroy an existent system, but rather enhanced the literacy levels, which can be used also for minority languages. The Third Republic early years were in fact the very summit of minority languages literature in France (Mistral, Nobel prize 1904). The use of the minority languages was killed by the rural-urban shift of the 1930', which cut off young people from the rural, minority-languages speaking, parents and grandparents. The villages spoke occitan/breton/catalan, the city french. The best example is Alsace-Lorraine : the Alsatian cities spoke alsatian in the 19th c., and the german annexation enforced this cultural preeminence, so the rural-urban shift did not bring a disappearance of the alsatian language. In nearby Moselle, Metz was a french-speaking city already in the 19th c., so, even with the german schooling of 1870-1918, the rural-urban shift made the francic languages very minor ones.