A bigger Netherlands would have made king Willem I de Koning-Koopman (king-merchant) very happy, but this IMHO would only have been possible if Prussia is allowed to annex the entire kingdom of Saxony or at least has substantial compensation. Willem I main issue wasn't his economic policies, but his tendency to be a bit autocratic; although at the time of the Belgian Revolution (1830, Willem I was forced to recognize Belgium in 1839) the economy wasn't in the best shape.
Diplomatically Willem I also wasn't that successful, since in 1830 he didn't receive support from Prussia and/or Russia, but was internationally quite isolated.
Diplomatically Willem I also wasn't that successful, since in 1830 he didn't receive support from Prussia and/or Russia, but was internationally quite isolated.