For some reason I doubt the Netherlands would accept the loss of Maastricht. It had been part of the Netherlands since the end of 80-year war and one of the most important reasons for keeping the province of Limburg (you know, the appendix of the Netherlands). Still some compromise with Prussia could probably be made and Prussia would no doubt be happy with just Luxembourg and Liege.
Good observation, IIRC Talleyrand's original plan did assign Maastrict to Prussia, but no doubt the exact borders of the partition might change during negotiations.
Assuming the Netherlands keeps Flanders (or at least most of it, Brussels and probably Leuven and other places near the Walloon border that are now Dutch speaking would probably go to France) would mean a larger Franco-Prussian border and later a larger Franco-German border, assuming German unification isn't butterflied away (and lets assume that or else Susano will be angry).
Besides the fact I rather sympathize with Susano's feelings

, I see no reason why this should butterfly German unification away, quite the contrary. A more sated France, a slightly more powerful Prussia, France closer to the Rhine (that would make German minors less hesitant about unification), would all make Bismarck's job easier.
IMO, the issue here is different: given that an TTL Schiliffen Plan would go through French Wallonia, essentially, would France fortify the area as heavily as they did with OTL French Lorraine, which would butterfly Schliffen Plan away, and cause a Russia First strategy ? Anyway, no Belgium most likely means UK neutrality in WWI.
It is almost unavoidable that France and Germany go to war in the late 19th and early 20th century for the dominance in Europe. In this case the Netherlands will probably not get involved, going through it doesn't offer a very big advantage (at least in my opinion).
I agree. I also think a Dietsland Netherlands would be somewhat more sympathetic to Germany than OTL Belgium. Up to 1914, France was more or less the expansionist menace to the Dutch, not Germany, they had invaded under Lousis XIV and Napoleon.
I think a scramble for Africa will still happen, at least Africa will still be devided by the European countries although maybe not in an as 'civilised' way as happed at Berlin.
Shadow Over Fashoda ???
I think that (most) of the continent will end up in French hands, although parts could go to Portugal, Germany and Britain. (I do not think that the Netherlands would care one bit about it, so no Dutch congo as you sometimes see in maps in which the Netherlands keeps Belgium).
Well, Congo was the personal aggrandizement ploy of the Belgian King, so I agree. Dietsland will have its hands full colonizing Indonesia.
I hardly think Germany and the UK would allow France to gobble all or most of Africa, much less the Congo. They might try, but no doubt this would trigger a war with UK and Germany sometime in the 1880s-1890s. Such a rich area (the Congo basin) in the hands of a minor European monarch is one thing, to a major power like France is another. IIRC Cecil Rhodes was expanding the borders northward till he met with the southward expansion of Congo's borders in the midst of the Katanga mineral basin, I assume that the UK would simply colonize all of southeastern Congo. Portugal might expand the borders of NAgola eastward a bit but not too much, they would run into UK soon. Germany might make a good claim over Central and Eastern Congo, they would gain a really worthwhile African colony for a change. Might France cross the Congo river border and expand in western Congo ?