Anyways, how about Beglian Congo, French Congo, and a third of Tanganyika? Maybe throw in Portuguese Congo for the heck of it. I see the Junkeresque estates based upon coffee, rubber, and similar things. They might keep the regular subdivisions, while trying to replace French speaking notables with those willing to speak German.
Tanganyika's already German, unless you're implying they need to cede parts of it for gains elsewhere.
Uniting the Congos could be huge for economic development in that region.
Yeah, there's a lot of local colonial government to have to make to speak German in this case. A lot of people who might need to be replaced.