One thing we may see is more exploration of the interior of the Dutch East Indies a lot sooner, particularly Borneo and New Guinea. If one Dutch explorer can discover the high lake of Enaratoli, then traverse the length of the New Guinea Highlands including the Central Valley around Mt. Hagen, the Dutch will know that the interior of New Guinea is roughly 8000 feet (1.5 km) high, conducive to Dutch and Belgian farmers settling there, and with a sedentary agricultural population, but with large areas of fertile land lying fallow due to longstanding feuds and wars between villages and ethnic groups to boot. Similar areas open to settlement will be found on Suluwesi, but Borneo is a lot lower.
A united and early industrializing Netherlands (Germany did not start to industrialize as a unified nation until after 1870 and France was hampered by it's geography and lack of natural resources) might be inclined to challenge the UK earlier when it comes to the Boers in South Africa, since the Boers are ethnically Dutch, particularly after the Voortrek. I could see a united Netherlands establishing colonies at Walvis and Luderitz Bays, say 1845 and building a railroad across the fringes of the Kalahari Desert to the new South African Republic and Orange Vrystaat by 1850, establishing Dutch protectorates over both (and over their slavery) by then, as well as an additional outlet for Dutch-Belgian colonization. For make no mistake. Colonization will ease a lot of social pressure back home for the Netherlands, just as it does for the UK. And yes, the Dutch will get what we now call Zimbabwe, Zambia and possibly Malawi, Katanga and Kasai OTTL. It's the railroads (and later steam tractors) that make all the difference. Draft animals sicken and die from Sleeping Sickness in Africa. (So do people, but people can protect themselves). This limits travel to on foot with native bearers. With a railroad, one can go lots of places and haul enough freight to make a profit. (You just have to replace the ties often because of the termites or make the ties of reinforced concrete). And tractors can till what fertile soil is available where draft animals will die--good, as soon as steam tractors are developed, which is about the 1880s OTTL., maybe sooner ITTL because they are more needed in Africa).
So the Flemish weavers will continue to provide competition industrially for British weavers, since the Netherlands will be able to produce plenty of cotton. It will be rather hard on the Africans, though, who will start out slaves and end up the equivalent of serfs
It may be possible to plant cotton with a steam tractor, but a cotton harvester takes a much higher level of technology, one that was not reached in the US until the late 1930s.