Here's a couple of WI's that could seriously damage, if not destroy, the Empire as we know it, especially in tandem.
1) Change the outcome of the First American Rebellion. Either have it never happen at all, or have the fighting continue. Now, you're probably thinking, "Didn't the Americans win?" They got what they initially asked for, yes, but at the time the proposal was sent, the thinking in America was that it was too little, too late on account of all the blood that had been shed--if France hadn't dropped out of the fight because it had its own problems to deal with, the Americans would have gone for full independence. Either way, you delay the conception and implementation of the dominion system, and in the latter case you cut out the heart of Imperial North America.
2) Either get rid of Sir Nigel Berry-Thorne or prevent him from publishing A Treatise on the Fates of Civilizations (OOC: basically Guns, Germs, and Steel written in the 1820s). Sir Nigel's original treatise was severely full of holes, but it served a very important purpose: it was an explanation of why the world looked the way it did that didn't rely on "Der, maybe white people are just smarter than everyone else?" I know Sir Nigel didn't end racism with a stroke of the pen or anything, but he gave anti-racists a theory to fall back on--and therefore, a voice in science and politics.
But getting rid of him wouldn't just make the Empire more terrible, it could destroy it. There was nearly enough opposition to the Dominion of Nigeria and the Indian dominions IOTL to end them--now imagine a world that's even a bit more racist. (And, if you're doing the first POD, Sir Nigel can simply be butterflied away.) The Indian dominions were the last to be admitted, remember--people were afraid that "the British Empire" would become "India and her little buddies", and to a very limited extent were right; these days it's simply "the Empire" and Britain is simply four Dominions among many, after all.
1) Change the outcome of the First American Rebellion. Either have it never happen at all, or have the fighting continue. Now, you're probably thinking, "Didn't the Americans win?" They got what they initially asked for, yes, but at the time the proposal was sent, the thinking in America was that it was too little, too late on account of all the blood that had been shed--if France hadn't dropped out of the fight because it had its own problems to deal with, the Americans would have gone for full independence. Either way, you delay the conception and implementation of the dominion system, and in the latter case you cut out the heart of Imperial North America.
2) Either get rid of Sir Nigel Berry-Thorne or prevent him from publishing A Treatise on the Fates of Civilizations (OOC: basically Guns, Germs, and Steel written in the 1820s). Sir Nigel's original treatise was severely full of holes, but it served a very important purpose: it was an explanation of why the world looked the way it did that didn't rely on "Der, maybe white people are just smarter than everyone else?" I know Sir Nigel didn't end racism with a stroke of the pen or anything, but he gave anti-racists a theory to fall back on--and therefore, a voice in science and politics.
But getting rid of him wouldn't just make the Empire more terrible, it could destroy it. There was nearly enough opposition to the Dominion of Nigeria and the Indian dominions IOTL to end them--now imagine a world that's even a bit more racist. (And, if you're doing the first POD, Sir Nigel can simply be butterflied away.) The Indian dominions were the last to be admitted, remember--people were afraid that "the British Empire" would become "India and her little buddies", and to a very limited extent were right; these days it's simply "the Empire" and Britain is simply four Dominions among many, after all.